Polling by Lord Ashcroft has shown that a significant percentage of UKIP supporters are planning on voting tactically when it comes to their specific constituency.

Surveys were taken in a number of marginal constituencies to monitor the support for Labour and the Conservatives ahead of next year’s crunch poll.

With everything to play for, the importance of smaller parties is crucial in these marginal seats as well as their own target seats, including Brighton Pavillion for the Green Party and Great Grimsby and South Thanet for UKIP.

While Nigel Farage’s party have been polling consistently in the high teens after their huge successes in the European Elections and the subsequent two by elections caused by the defections of Douglas Carswell and Mark Reckless, when broken down it looks like there will be a drop in support in key constituencies where the party is not polling with the front runners.

According to the results, UKIP scored slightly lower than the headline rate when people were asked to think about their own constituency and how they would vote.

Of those who said they would vote UKIP in the standard question, 8% said they would vote Conservative when it came to their own constituency, 5% said Labour and 5% said they did not know what they would do. Fourteen per cent of 2010 Tories who named UKIP in the first question said they would vote Conservative again when asked about their own seat.

This is bound to be because of the first past the post system which makes it incredibly difficult for new parties to emerge. With so much to play for in the 2015 General Election for people whose main priorities are controlling immigration and leaving the EU they have to way up the risks of voting for their favourite party or lending their vote to the Conservatives (especially in the South and West) as a political ‘each way’ bet on securing a referendum.

Only just over half (52%) of Conservative defectors to UKIP, and only 60% of Lib Dem defectors to Labour, ruled out returning to their 2010 parties at the next election.

The surveys were taken in constituencies with Tory majorities over Labour of between 7.1 per cent and 8.5 per cent. It found that five of the eight would stay in Conservative hands, one (South Swindon) would be a tie and Labour would gain Stevenage and Ealing Central and Acton.

Key for Labour are the battle grounds between red and purple. Four seats; Great Grimsby, Dudley North, Plymouth Moor View and Rother Valley show Labour at “critical” or “high risk” of a direct, successful challenge from UKIP.

UKIP were ahead by up to six points on the standard voting intention in three seats, with Labour pulling into the lead when they were asked specifically about their own constituencies, with tactical voting rearing its head again but in the opposite direction to before.

In the seats as a whole the swing to UKIP was 13.5% and Great Grimsby looks to be a real opportunity for UKIP candidate Victoria Ayling to secure her place in the history books.

With tactical voting looking to play such a key role in the May election, it seems the party spin machines will need to be working overtime to counter talk of ‘wasted votes’ or ‘letting the other side in’. But with with momentum that UKIP has built up it is by no means certain that particularly in the Labour seats they are targeting in the East of the country, there can’t be a strong purple tide on election night.

For the Conservatives, things are looking more positive than they could be even though in the seats polled, Labour were slightly ahead. A well run campaign with tight messaging could see the UKIP voters lending Mr Cameron their support to keep out their mutual opponent of Ed Miliband who is facing a battle on two fronts as he fights for the keys to Number 10.