Almost one third of British voters are not planning on backing any of the three main parties, according to a new poll.
A ComRes poll for the London Independentput support for "others" at 30 per cent, up 18 per cent since before the expenses row erupted.
The rating is neck and neck with the Tories - who have plummeted 15 per cent from the equivalent poll last month.
Labour has dropped four points to 22 per cent, while the Liberal Democrats were up one on 18 per cent. The Greens were on 8 per cent, Ukip on 7 per cent, the BNP 3 per cent, the Scottish National Party 2 per cent, Plaid Cymru 1 per cent and other smaller parties or independents 9 per cent.
Meanwhile, an Ipsos Mori poll found support for Labour has plunged by 10 points in the past month, and the party is now running neck and neck with the Liberal Democrats.
The dramatic slump in Labour's fortunes has allowed the Conservatives to pull 22 points clear, according to the research.
While support for all the main parties has declined in the aftermath of the MPs' expenses scandal, Labour appears to have fared the worst by far.
The Ipsos Mori poll put the Tories on 40 per cent, down one since the same survey last month. But Labour was down 10 points, putting the party on the same support as the Lib Dems, who were down four on 18 per cent.
At the same time, support for minor parties has doubled in the past month to 24 per cent, including 7 per cent for the UK Independence Party, 6 per cent for the Greens and 4 per cent for the British National Party.
The poll will harden expectations that Labour will be given a drubbing in Thursday's European and local elections.
PA