Ed Miliband edges out Nicola Sturgeon in post-debate poll
The snap poll by Survation handed the Labour leader 35%, compared to 31% for Ms Sturgeon and 27% for Nigel Farage.
Green leader Natalie Bennett got 5%, while Plaid Cymru leader Leanne Wood had 2%.
However, the Survation poll, conducted for the Daily Mirror, found that Ms Sturgeon overtook Mr Miliband when participants were asked who performed the best.
Mr Miliband led on who voters thought would make the best prime minister and who had the best policies on the deficit, while Mr Farage led on immigration and defence.
Ms Sturgeon was judged to have answered the questions the best and to have had the most appealing personality.
The debate, held by the BBC, covered topics including immigration, defence, the deficit, post-election deals and housing.
Through the course of the debate, the leaders also touched on the NHS and foreign policy.