Almost a third of voters are planning to cast their ballot tactically in the general election to keep out a candidate or party they dislike, a poll has found.

Experts now say the 12 December election could see tactical voting being carried out on a scale never seen before, potentially deciding the outcome and determining whether the UK will finally leave the EU.

Campaigner Gina Miller believes that around 40 per cent of Remain supporters need to vote tactically to prevent a Conservative government from forcing Brexit through in January.

Polls – including the latest BMG survey for The Independent, which has Remain ahead by a margin of 54 to 46 – now consistently show the majority of Britons are in favour of staying in the EU.

The scale of tactical voting required has increased sharply in response to Nigel Farage’s decision not to stand Brexit Party candidates in 317 Tory constituencies. A further 39 Brexit Party candidates in seats held by Labour or the SNP were withdrawn as nominations closed on Thursday, which Ms Miller said had reduced the number of seats where tactical voting has real potential to make a difference from 68 to 51.

General election: Facts and figures Show all 79 1 /79 General election: Facts and figures General election: Facts and figures General election 2019 opinion polls General Election 2019 opinion polls. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Estimated declaration time General Election 2019 estimated declaration times. See story POLITICS Election. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures 'Big beasts' at risk General Election 2019 'big beasts' at risk. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Smallest majorities at 2017 general election Smallest majorities at 2017 general election. See story POLITICS Election. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures Turnout at UK general elections Turnout at UK general elections. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures General election 2019 poll of polls General Election 2019 poll of polls. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Vote shares at general elections since 1945 Vote shares at general elections since 1945. See story POLITICS Election. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures Seats to watch in North-west England General election 2019 seats to watch in North-west England. See story POLITICS Election NorthWest. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Women MPs at UK general elections Women MPs at UK general elections. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures General election 2019 leaders' visits - Boris Johnson and Jeremy Corbyn General Election 2019 leaders' visits. See story POLITICS Election Visits. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Boris Johnson's campaign visits so far General Election 2019: Boris Johnson's campaign visits so far. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Jeremy Corbyn's campaign visits so far General Election 2019: Jeremy Corbyn's campaign visits so far. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Pound v dollar Pound v dollar. See story POLITICS Election. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures General election 2019 opinion polls in Wales General Election 2019 opinion polls in Wales. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Seats to watch in London General election 2019 seats to watch in London See story POLITICS Election London. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Seats to watch in Wales General Election 2019 seats to watch in Wales. See story POLITICS Election WalesSeats. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Seats to watch in Eastern England General election 2019 seats to watch in Eastern England. See story POLITICS Election Eastern. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures General election 2019 leaders' visits so far General Election 2019: leaders' visits so far. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Seats to watch in south-east England General Election 2019 seats to watch, south-east England. See story POLITICS Election SouthEast. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures General election 2019 leaders' visits General Election 2019 leaders' visits. See story POLITICS Election Visits. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Historic Labour seats at risk General Election 2019: historic Labour seats at risk. See story POLITICS Election Historic. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Opinion polls (one week to go) v election result 2017 Opinion polls v election rsult 2017. See story POLITICS Election Polls. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures General election 2019 polls in Scotland General Election 2019 opinion polls in Scotland. See story POLITICS Election Poll Scotland. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Opinion polls (one week to go) v election result 2015 Opinion polls v election result 2015. See story POLITICS Election Polls. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Seats to watch in West Midlands General election 2019 seats to watch in the West Midlands. See story POLITICS Election WestMidlands. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Bellwether seats Bellwether seats at UK general elections. See story POLITICS Election Bellwethers. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Conservative top targets General Election 2019 Conservative top targets. See story POLITICS Election Conservatives. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures General election 2019 polls in London General Election 2019 opinion polls in London. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Leaders' approval ratings, July-December Leaders' approval ratings. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Seats to watch in Yorkshire General election 2019 seats to watch in Yorkshire. See story POLITICS Election Yorkshire. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures General election 2019 timetable General Election 2019 timetable. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Labour top targets General Election 2019 Labour top targets. Infographic PA graphics PA Graphics Press Association Images General election: Facts and figures Seats to watch in north-east England General Election 2019 seats to watch, north-east England. See story POLITICS Election NorthEast. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures When parliamentary seats last changed hands When parliamentary seats last changed hands. See story POLITICS Election Seats. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures Seats to watch in the East Midlands General election 2019 seats to watch in the East Midlands. See story POLITICS Election EastMidlands. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Seats to watch in south-west England General election 2019 seats to watch in south-west England. See story POLITICS Election SouthWest. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Planned increase in day-to-day departmental spending General Election 2019 planned increase in day-to-day departmental spending. See story POLITICS Election IFS. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Corporation tax rates General Election 2019 corporation tax rates. See story POLITICS Election IFS. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Opinion polls (two weeks to go) v election result 2017 Opinion polls v election result 2017. See story POLITICS Election Polls. Infographic by PA Graphics. PA Graphics Press Association Images General election: Facts and figures Opinion polls (two weeks to go) v election result 2015 Opinion polls v election result 2015. See story POLITICS Election Polls. Infographic by PA Graphics. PA Graphics Press Association Images General election: Facts and figures Hospital admissions in England for poisoning by drug misuse. See story POLITICS Drugs. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures Applications to register to vote Applications to register to vote. See story POLITICS Election Voting. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures How many women MPs could there be after the election? How many women MPs could there be after the election? See story POLITICS Election Women. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures General election 2019 opinion polls in Wales General Election 2019 opinion polls in Wales. See story POLITICS Election. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures A comparison of the length of the manifestos of the main parties A comparison of the length of the manifestos of the main parties. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Mentions of key words in the main party manifestos Mentions of key words in the main party manifestos. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Mentions of key words in the main party manifestos Mentions of key words in the main party manifestos. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Leaders' approval ratings, July-November Leaders' approval ratings. See story POLITICS Election. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures Council houses built in the UK 1951-2018 Council houses built in the UK 1951-2018. See story POLITICS Election Labour Housing. Infographic from PA graphics PA Graphics Press Association Images General election: Facts and figures Council houses built in the UK Council houses built in the UK. See story POLITICS Election Labour Housing. Infographic from PA graphics Press Association Images General election: Facts and figures Opinion polls (three weeks to go) v election result 2015 Opinion polls v election result 2015. See story POLITICS Election Polls. Infographic by PA Graphics. PA Graphics Press Association Images General election: Facts and figures Opinion polls (three weeks to go) v election result 2017 Opinion polls v election result 2017. See story POLITICS Election Polls. Infographic by PA Graphics. PA Graphics Press Association Images General election: Facts and figures General election 2019 target seats General election 2019 target seats. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Lib Dem targets General Election 2019 Lib Dem targets. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures SNP targets General Election 2019 SNP targets. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Plaid Cymru targets General Election 2019 Plaid Cymru targets. See story POLITICS Election Plaid. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures Prime ministers with shortest time in office Prime ministers with shortest time in office. See story POLITICS Election PrimeMinister. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Applications to register to vote Applications to register to vote. See story POLITICS Election Voting. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Major toll roads & bridges in Great Britain Major toll roads & bridges in Great Britain. See story POLITICS Election Labour Tolls. Infographic from PA graphics PA Graphics Press Association Images General election: Facts and figures Police workforce in England and Wales Police workforce in England and Wales. See story POLITICS Election Tories Knife. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Police officers in England and Wales Police officers in England and Wales. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Police-recorded homicides in England and Wales Police-recorded homicides in England and Wales. See story POLITICS Election Tories Knife. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures Knife crime offences recorded by police in England and Wales Knife crime offences recorded by police in England and Wales. See story POLITICS Election Tories Knife. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures Opinion polls in 2019 Opinion polls in 2019. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Number of candidates per seat Number of candidates per seat at the 2019 General Election. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Candidates standing in the 2019 General Election Candidates standing in the 2019 General Election. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Candidates at UK general elections since 1979 Candidates at UK general elections since 1979. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Women candidates at the 2019 General Election Women candidates at the 2019 General Election. Infographic from PA Graphics. Charlotte Hodges Press Association Images General election: Facts and figures Prime ministers with smallest constituency majorities to defend Prime ministers with smallest constituency majorities to defend at a general election. See story POLITICS Election Majority. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Cost of administering polls since 2010 Cost of administering polls since 2010. See story POLITICS Election Cost. Infographic by PA Graphics. Embargoed to 0001 Wednesday November 6 PA Graphics Press Association Images General election: Facts and figures People's Vote group priority list of recommended candidates in key target seats People's Vote group revealed its priority list of recommended candidates in key target seats. See story POLITICS Election Vote. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures MPs retiring from the House of Commons at general elections MPs retiring from the House of Commons at general elections. See story POLITICS Elections. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Lib Dems/Plaid Cymru/Green pact in Wales Lib Dems/Plaid Cymru/Green pact in Wales. See POLITICS Election Pact Seats. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Lib Dems/Green pact in England, seats where Greens have stood down in favour of Lib Dems Lib Dems/Green pact in England, seats where Greens have stood down in favour of Lib Dems. See story POLITICS Election Pact Seats. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Lib Dems/Green pact in England Lib Dems/Green pact in England. See story POLITICS Election Pact Seats. Infographic by PA Graphics PA Graphics Press Association Images General election: Facts and figures Nationality of NHS workforce in England Nationality of NHS workforce in England. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Proportion of NHS workforce in England who are not UK nationals Proportion of NHS workforce in England who are not UK nationals. See story POLITICS Election. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Long-term net migration to the UK Long-term net migration to the UK. See story POLITICS Election Immigration. Infographic PA Graphics PA Graphics Press Association Images General election: Facts and figures Shortest parliamentary sessions since First World War Shortest parliamentary sessions since First World War. See story POLITICS Election Dissolution. Infographic PA Graphics PA Graphics Press Association Images

There was evidence in the latest poll that Brexit backers are as ready as Remainers to use their vote tactically. Overall, 31 per cent said they would vote for the candidate best positioned to defeat a party they dislike, against 61 per cent who will back their preferred candidate regardless of their likelihood of winning. Some 31 per cent of Remainers and 30 per cent of Brexiteers were ready to vote tactically.

Campaigners for electoral reform said the findings bolstered the case for change to a first-past-the-post system which is driving parties to form electoral pacts and voters to back second-choice or third-choice candidates.

And the poll suggested that voters – who rejected a move to the alternative vote system in a 2011 referendum – may be ready for reform. Some 43 per cent said they would back a more proportional system, against just 18 per cent who oppose it.

In a clear indication that many feel the current system means their vote is wasted, 43 per cent said they felt their vote would have little or no impact on the outcome in their constituency, against 44 per cent who said it would be fairly or very significant.

Polling guru John Curtice, of Strathclyde University, said the election was shaping up as an “unpopularity contest” between Boris Johnson and Jeremy Corbyn, who each record historically high levels of dissatisfaction among voters. With the likelihood of a Labour majority “close to zero”, voters were effectively being asked to choose between a Conservative administration to deliver Brexit or a hung parliament leading to a second EU referendum, he said.

He added: “What will be crucial will be how much anti-Tory tactical voting there is.

“A relatively small number of voters doing it in the right places can make a difference. My judgement at the moment is that with Tories in a 10-point lead, it won’t be enough. But if the lead comes down a bit, maybe it will.”

Polling expert John Curtice has described the coming election as an unpopularity contest (BBC)

Ms Miller told The Independent that awareness of tactical voting was far higher than at the last election in 2017, particularly among younger voters. Some 40 per cent of 18- to 24-year-olds in the latest poll said they were considering a tactical vote, against 26 per cent of over-65s.

She said the response to her Remain United website, which offers advice on how to use your vote most effectively to stop Brexit, has been “extraordinary”, with her organisation recording more than 11 million online interactions with voters.

“Tactical voting is much more in the mindset of voters than it was in 2017,” she said.

“We have seen record numbers of young people registering to vote over the past six months and they are very open to the idea of tactical voting. They are talking about it on Facebook and Instagram, which we didn’t see in 2017.”

Tactical voting has far more potential to alter the outcome of the election than the pact between the Remain-backing Liberal Democrats, Greens and Plaid Cymru to stand down candidates in one another’s favour, said Ms Miller.

Gina Miller has set up a tactical voting website called Remain United (EPA)

“The Unite to Remain pact might make a difference in three or four seats,” she said. “In this election, it is all about tactical voting not about party pacts on the Remain side.”

But she cautioned that anyone aiming to vote tactically to block a Johnson majority must keep themselves informed to make sure their actions count.

In 1997 – the last election when tactical voting is believed to have played a major part – it is thought to have accounted for around nine additional Labour wins and 15 to 20 Lib Dem victories, Ms Miller said.

But she added: “Independent research has shown that about 30 per cent of tactical votes in 1997 went the wrong way. We need about 40 per cent of Remain supporters to vote tactically and to do it in the right way to prevent a Conservative majority.”

Ms Miller's remainunited.org site is seeking to help Remainers make their vote count by constantly updating recommendations in response to the developing campaign and frequent 6,000-person polls, she said.

And she will be micro-targeting undecided potential tactic voters with online ads as polling day approaches.

But would-be tactical voters must weigh up for themselves the differing recommendations offered by Ms Miller’s operation and two alternative Remainer advice sites at getvoting.org and tactical-vote.uk.

Support free-thinking journalism and attend Independent events

The director of research and policy at the Electoral Reform Society (ERS), Jess Garland, said the confusion in voters’ minds was the result of a first-past-the-post system which did not reflect the realities of modern political life.

She insisted the answer to the issue was not more sophisticated tactical voting operations, but the introduction of a proportional system, such as the Single Transferable Vote option which the ERS favours.

“We are seeing a huge fragmentation in the party system but we have an electoral system that is designed for two-party politics,” Ms Garland told The Independent.

“This was happening before Brexit but it’s been put into starker relief by Brexit. For the first time in my lifetime, it’s forcing parties to make pacts with other parties and voters to back their second or third choice.

“Both parties and voters are having to change the way they act to try to game the system, and the system is cracking under the strain. It will produce very perverse results.

“Tactical voting websites are trying to paper over the cracks in the system, but voters shouldn’t be driven to play political games like this. They should be able to vote for who they want to vote for.”