There is a BPIX poll in tomorrow’s Mail on Sunday which has topline figures of CON 31%(-7), LAB 28%(-3), LDEM 32%(+12). That’s the biggest drop for Conservatives so far, and the biggest surge for the Lib Dems – and it puts the Liberal Democrats up in first place. The Lib Dems were in equal first place in a poll back in 2003, but I think you need to go back to around 1982 to find polls with them (or their predecessor parties) consistently in first place (Update – Tom in the comments has flagged up one poll from 1985 that had the Alliance ahead)
As with ComRes today and YouGov yesterday, all three parties are within 4 or 5 points of each other, so realistically if the polls remain like this it shouldn’t be a surprise to see polls with any of the three parties in the lead.
There is also a OnePoll survey in the People, that shows CON 27%, LAB 23%, LDEM 33%. I have still not confirmed whether these polls have any proper attempt at sampling or political weighting, and would treat it with great scepticism.
There is at least YouGov still to come tonight.