By politics.co.uk staff
The Liberal Democrats could be pushed back to fourth place in this Thursday's Barnsley Central by-election, a poll suggests.
Pollsters Survation tipped Labour's candidate Dan Jarvis to hold the seat with an increased majority, after former MP Eric Illsley was convicted for illegal expenses claims.
The research for the Mail on Sunday newspaper suggested Mr Jarvis, a former soldier who served in both Iraq and Afghanistan, would take an enormous 63% of the vote - significantly up from Mr Illsley's already impressive 47.3%.
Any slip from the narrow second place secured by Lib Dem Christopher Wiggin last May is likely to be interpreted as another indication of the failing popularity of the coalition government's junior party.
It follows the Lib Dems' failure to take Oldham East and Saddleworth from Labour in January's by-election - despite former immigration minister Phil Woolas' disgrace after a special court found him guilty of breaching election laws.
Last May the Lib Dems took 6,394 votes compared to the Conservatives' 6,388. Mr Illsley won 17,487 votes.
Survation predicted the Tories' share of the vote would slip to 13% but the Lib Dems would collapse to just six per cent, behind Ukip candidate Jane Collins on nine per cent.
The poll even suggested the BNP's Enis Dalton, who polled four per cent, could overtake the Lib Dems.
That could be disastrous for Nick Clegg, who has attracted criticism from some sections of the press for his Swiss skiing break while the prime minister masterminded the evacuation of British nationals from Libya.
Survation questioned 507 registered voters in Barnsley Central at the end of last week.
Full list of candidates for the Barnsley Central by-election
Dominic Carman (Liberal Democrat)
Jane Collins (Ukip)
Enis Dalton (BNP)
Michael Val Davies (Ind)
Tony Devoy (Ind)
Howling Laud Hope (Official Monster Raving Loony)
James Hockney (Conservative)
Dan Jarvis (Labour)
Kevin Riddiough (English Democrat)