Deputy Prime Minister Nick Clegg has come under renewed pressure from within his own party after senior figures warned he was not "indispensable" and could be replaced by Business Secretary Vince Cable.
Andrew Bridgwater, vice-chairman of the Lib Dem's Devon and Cornwall regional party and chairman of its education association, called on Mr Clegg to go.
Speaking to the Independent on Sunday, he said: "The sooner Nick resigns and creates a vacancy for Vince, the better.
"To put it bluntly, I would encourage Vince Cable to stand for the leadership to take us into the next election."
Adding to the instability, veteran MP Adrian Sanders told The Sunday Times that Mr Clegg needed to stop "bumbling along worrying about the future".
Meanwhile, Lib Dem peer Lord Smith of Clifton described him as "a cork bobbing on the waves" with "no strategic vision at all".
He told the BBC: "It's not as if Clegg is indispensable. Vince Cable possesses the appeal and the credibility to lead the Liberal Democrats into the next election."
The comments come after one of Mr Cable's closest allies, Lord Oakeshott of Seagrove Bay, warned last week that the party may have to consider a change of "management and strategy" if it is to stand any chance at the next election.
An ICM Research/Guardian poll last month said 15% of voters had indicated they would vote for the Lib Dems at the next general Election, up 1% from the previous month.