Clegg sets his sights on Downing Street

By Tim Castle

BOURNEMOUTH (Reuters) - Liberal Democrat leader Nick Clegg on Wednesday declared his ambition to become prime minister, as party aides said private polling indicated that the next election was "wide open."

Clegg, 42, told delegates at their autumn conference in Bournemouth that he sought the top job because he had spent half a lifetime imagining a better society "and I want to spend the next half making it happen."

He made no reference to the possibility of winning power through a coalition or pact in a hung parliament, which analysts say is the party's best chance of tasting power, given that it now only holds 63 of parliament's 646 seats.

Polls say the Conservatives are set to sweep Labour from power in a general election, with the Liberal Democrats trailing in third on a 20 percent vote.

But LibDem party aides said private polling conducted over the summer showed many people were undecided over which party to support in the election expected next May and that the result was far from certain.

Clegg, positioning the Liberal Democrats as a credible alternative for government, said his party was replacing Labour as the "dominant voice of progressive politics."

"We are the alternative to a hollow Conservative Party that offers just an illusion of change," he added. "Let me tell you why I want to be prime minister. It is because I want to change our country for good."

Dismissing Labour as "dying on its feet," Clegg focussed his attack on the Conservatives, who are the main challengers in 13 of the Liberal Democrats' 20 most vulnerable seats and would win them all if current national polls are reflected locally.