As the party leaders spent the day delivering their final messages, a series of polls showed that the Conservatives and Labour are still locked in an extremely tight race for Downing Street.
Ahead of arriving in Scotland, Tory Prime Minister David Cameron used his last major interview on the Today program to warn that Ed Miliband had used “a con trick” on voters about ruling out a deal with the SNP.
The Nationalists appear set to win more than 50 seats taking out most or all of 41 Scottish seats and Mr Cameron claimed Labour “will need to deal with them” if they want to hold power.
Meanwhile arriving in Bearsden Lib Dem leader Nick Clegg repeated his warnings of a second election if either the Tories or Labour try to press ahead with a minority government.
Mr Clegg claimed the Lib Dems would be the “surprise story” of election night, doing better than pollsters had predicted.
In a speech to activists in East Dunbartonshire, he said: “At the beginning of this campaign we were written off and yet tomorrow, when the polls close, the Liberal Democrats will be the surprise story of this General Election campaign because we are going to win.”
The speech was interrupted by a passing motorist shouting “Liar”, while before Mr Clegg spoke a jogger yelled “Come on the SNP” at Lib Dem activists.
Ms Sturgeon told Scottish voters that a large SNP contingent in Westminster will make “Scotland heard like never before” and said that they had “24 hours to end austerity”.
Mr Miliband is campaigning across Lancashire and Yorkshire where he is claiming that a fresh coalition between the Conservatives and Liberal Democrats poses a “huge risk” to working families.
He is accusing both parties of defending the non-dom tax avoidance rule and preparing to “protect the privileged few” if they remain in power.
“I’m going right up to the line, right down to the wire talking about the issues that matter to the British people, which is the NHS, their family finances, whether they can pay the bills at the end of the month, those bread-and-butter issues that matter most to the British people,” he told broadcasters.
Asked if he really believes he is going to be prime minister, he replied: “I’m optimistic but it will be in the hands of the people come tomorrow and I know the people will make the right judgment.
“And, I hope people make a judgment on the basis of what’s best for them and their family because I’m not just asking people to vote Labour, I’m asking people to vote to put their family first in this election.
“I think on the ballot paper is the National Health Service, tax credits and child benefits, family finances, our young people, and that’s why I ask people to vote Labour.”
But as they delivered their messages the polls suggested the result is still highly uncertain.
A ComRes poll had the Tories in a three-point lead - gaining two to reach 35 per cent while Labour dipped a point to 32 per cent.
But a YouGov poll had the two parties tied on 34 per cent as they enter the final days of campaigning, while the final poll from Lord Ashcroft has the Conservatives on 32 per cent and Labour on 30 per cent.
A Survation poll also revealed a deadlock as election day looms, with Labour on 34 per cent and the Conservatives 33 per cent, both unchanged.
The survey of 1,011 adults between May 3 and 4 by ComRes had Ukip on 14 per cent, their highest vote share since January in a ComRes telephone poll. The Lib Dems were also up one on 9% and the Greens on four per cent, down three.