Nick Clegg will today attempt to counter the Tory threat to dozens of Liberal Democrat MPs by insisting that voting Conservative is not the only way to remove Gordon Brown from Downing Street.
The Lib Dem leader will put his party on general election alert as he closes a conference overshadowed by controversy over his plans for a "mansion tax" and in-fighting over tuition fee policy.
His closing address follows protests from Lib Dem MPs that they were not consulted by the leadership over proposals to impose higher taxes on the owners of £1m-plus properties.
Clegg aides insist that the party is optimistic and upbeat ahead of the election that will have to take place within the next nine months. But privately they fear that Lib Dem seats across the South and South-west of England are highly vulnerable to the Conservative advance under David Cameron.
Mr Clegg will appeal to voters not to support the Tories as the only way of ousting Labour from office. The choice at the next election is fake change from the Conservatives or real change from the Liberal Democrats," he will insist. "Power is yours to give to whoever you choose. So don't turn away, don't stay at home, don't vote Conservative just because you think it is the only option. This is Britain: we don't settle for second best because we think it is inevitable."
He will tell the Bournemouth conference: "I know there are a lot of people who agree with what we've got to say, but who still don't vote Liberal Democrat. You don't think we are contenders. I urge you to think again. If you don't agree with our policies, if you don't want big change in Britain, then don't vote for us. But if you like what you hear, if you share our vision for a different kind of future, then go with your instincts."
Tensions within Lib Dem ranks over the direction of the party were laid bare yesterday as MPs confronted Vince Cable, the Treasury spokesman, over the "mansion tax". One frontbencher complained that they had been left to fend off questions about a policy that was news to them.
There were also protests that Mr Clegg, who was not present at the meeting, was failing to consult his foot-soldiers adequately.
After the heated one-hour confrontation in the conference headquarters hotel, one MP protested that the policy was "complete codswallop", while another said Mr Cable had been "seriously damaged" by the episode.
Among those who were left out of the loop was Julia Goldsworthy, the party's local government spokeswoman. One frontbencher, who also confirmed he had been kept in the dark over the policy, told The Independent: "Julia should have been informed. It clearly affects her portfolio. If I had been treated like that I would have been furious."
Frustrations with the leadership spread hours later to the conference hall, with delegates and MPs losing patience over Mr Clegg's downbeat message over "savage cuts" and his refusal to rule out shelving the party's commitment to scrapping tuition fees.
There were also growing accusations that Mr Clegg and Mr Cable were trying to impose their pet projects on the party, with one delegate complaining that policies should not come "direct from Nick Clegg".