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The general election campaign is drawing to a close with party leaders making late bids to break the deadlock in the polls.

Prime Minister David Cameron said the country was "stronger than it was five years ago" but there was "more to do".

Ed Miliband urged people to vote "to reward hard work in our country again" while Nick Clegg said the Lib Dems would offer "stability and decency".

Polls suggest no party will win enough seats for an outright majority.

An ICM survey for the Guardian put the Conservatives and Labour level on 35%.

BBC deputy political editor James Landale said there would be "pretty fundamental questions" on the ballot paper when polls open at 07:00 BST.

He added: "The outcome may be uncertain but the stakes are incredibly high."

On the last day of campaigning:

The main party leaders have been criss-crossing the country in their battle buses as they attempt to drum up support ahead of Thursday's poll.

Media playback is unsupported on your device Media caption David Cameron: Tories will build on "strong foundation" of last five years

Media playback is unsupported on your device Media caption Ed Miliband: "I will put working families first"

Media playback is unsupported on your device Media caption Nick Clegg: Liberal Democrats will give "a brain and a heart" to the UK

Media playback is unsupported on your device Media caption Nigel Farage: Voters have been "cheated" out of a proper debate

After starting the day in Mid Wales, Mr Cameron stopped off in the west Midlands before heading to Chester and Lancaster. He is set to end the day by visiting Carlisle and Dumfriesshire, where the party holds its only seat in Scotland.

Meanwhile, Mr Miliband is visiting a succession of Conservative-held marginal seats in Lancashire and west Yorkshire such as Colne Valley, Pendle and Elmet and Rothwell.

Mr Clegg, who set off from Land's End on Tuesday, is heading to John O'Groats through Scottish constituencies his party is hoping to retain such as East Dunbartonshire and Inverness, Nairn, Badenoch and Strathspey.

The prime minister, whose Conservative Party won 307 seats in 2010, has renewed his attack on the possibility of a minority Labour government propped up by the Scottish National Party (SNP), saying it would face "huge questions of credibility".

Mr Cameron insisted a Conservative victory was "within reach" but insisted that he would put "the country first" whatever the outcome of Thursday's poll by working to provide "strong and stable" government.

Image copyright Reuters Image caption The Labour leader is focusing on marginal seats in the north-west of England

Image copyright PA Image caption Nicola Sturgeon has urged Scottish voters to "unite" behind the SNP

Image copyright Getty Images Image caption The prime minister started the day discussing agriculture at a family farm in Mid Wales

Image copyright PA Image caption While Nick Clegg is continuing his 1,000-mile tour from Land's End to John O'Groats

Image copyright Reuters Image caption And senior Conservatives have also found time to visit a bakery

Image copyright PA Image caption Nigel Farage has said he will be "for the chop" as UKIP leader if he does not win his Thanet South seat

Image copyright Getty Images Image caption The Green Party says it is offering "real change from business as usual"

Image copyright AFP Image caption While preparations are under way in the UK's 650 constituencies - such as in Rathlin Island - for Thursday's poll

The Conservative leader said he had achieved a lot since 2010 but was "not satisfied" with current levels of deprivation and educational under-achievement in parts of the country and wanted to push harder on welfare and schools reforms.

"Is our country stronger than it was five years ago? Yes," he told BBC Radio 4's Today. "Is there more to do? Yes. But I would say stick with the team that is turning things around."

Policy guide: Key priorities What are the top issues for each political party at the 2015 general election?

Mr Miliband, who is looking to improve on the 258 seats Labour won in 2010 under the leadership of former Prime Minister Gordon Brown, said his party would have more activists on the ground on Thursday helping to get out the vote than the other parties combined.

He warned that another Conservative-led government "propped up by the Lib Dems" would "raid family budgets and cut the NHS".

"This is the clearest choice that has been put before the British public for a generation. Between a Tory government that is for the privileged few and a Labour government that puts working people first."

Analysis by BBC political editor Nick Robinson

Image copyright North One television

This is isn't how this election was meant to go.

It's been marked by the lack of confidence felt by our political leaders rooted in the overwhelming lack of trust felt by most voters.

Why else would David Cameron promise to pass a law - not mentioned in his own manifesto - which would stop himself putting up taxes he's long pledged not to raise?

Why else would Ed Miliband resort to "carving in stone" pledges so broad and so general that it would be almost impossible to judge whether they've ever been broken?

Why else would we see the relentless political cross-dressing as the Tories promised to become the party of the workers and Labour the party of economic responsibility?

The two big parties have even been too nervous to follow the classic campaign themes.

Read Nick's full blog

Labour's deputy leader Harriet Harman said her party could still win what she described as a "watershed election" for the NHS: "I don't think it (the health service) will survive as people want it to survive, and need it to survive, under the Tories."

Mr Clegg, whose Liberal Democrats are battling to keep hold of the 57 seats they won five years ago, is visiting marginal Scottish seats under threat from the SNP, telling voters: "You face the biggest political decision of your life."

Media playback is unsupported on your device Media caption Natalie Bennett: Green Party offering politics "built on values and on principles"

Media playback is unsupported on your device Media caption Leanne Wood says Plaid Cymru is 'best placed' to fight for Wales

He has sought to position his party as keeping any future coalition government "anchored" in the centre ground.

Without the Lib Dems, he said, "Labour or the Conservatives will be left to run a messy and unstable minority government, dependent on the SNP on the one hand or UKIP and the DUP on the other".

The SNP's Nicola Sturgeon, whose party is forecast to take a number of seats from Labour and the Lib Dems in Scotland, said the vote was an "opportunity for us to come together, to unite and link arms as one Scotland and vote SNP to make our voice heard".

Image copyright Getty Images

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