Tory peer Lord Ashcroft's latest round of polls show Nigel Farage two points behind his Conservative opponent Craig Mackinlay in the key battleground constituency of South Thanet.
The Ukip leader has said he will resign as party leader if he fails to take the Kent seat. The Tories have marginally increased their lead over Ukip in South Thanet, from one point in November 2014 to two points in April.
The Ashcroft poll finds that the Labour vote share in South Thanet is falling as the Tories are rising, suggesting Labour supporters may vote tactically to keep Farage out. It should be stressed that the Tory lead is within the margin of error so there is still all to play for.
Lord Ashcroft's last set of constituency polls also brought bad news for Ukip, with the party's support declining in two of the four constituencies surveyed.
In Nick Clegg's seat of Sheffield Hallam, the Lib Dem leader has also improved his chances of re-taking the seat. Nick Clegg is on 36 per cent, just one point behind his Labour challenger Oliver Coppard. In March Labour had a lead of two points.
Like South Thanet, Sheffield Hallam is exhibiting shades of tactical voting. Almost a third of people who voted Tory in 2010 say they will support Clegg on election day.
The last marginal constituency to be examined was South Swindon - a Labour-Tory marginal. Here, the voting intention has improved for the Conservatives - they took a one point lead over Labour with 37 per cent, from a tie in March. But England hasn't been the only place for important polls today.
Earlier an STV News poll conducted by Ipsos Mori puts the SNP on 54 per cent - a massive 34 points ahead of Labour.
The Electoral Calculus website forecasts that if this poll was reflected on polling day, Nicola Sturgeon's party would capture all 59 Scottish seats. The Tories have increased their support in Scotland by five points to 17 per cent, the poll suggests.