Sir Vince Cable has said the Lib Dems need to "start winning again", promising "bold, radical" policies on housing, education and wealth taxes.
Ahead of his first leader's speech to conference, he told the BBC the party may be at a "low base" electorally but was "totally" united over Brexit.
Common sense moderation was a virtue at a time of political extremes, he said.
But there was also big thinking going on, he added, in terms of the future of tuition fees and vocational education.
The 74-year old, who was elected unopposed this summer after the resignation of Tim Farron, said he was relishing the challenge of leading the party, which he said was fully behind him.
He raised eyebrows on Sunday by suggesting that although the Lib Dems only have 12 MPs, he could be the next prime minister, given the current volatile state of British politics.
Expanding on that theme, he told the BBC's chief political correspondent Vicky Young that although the party's vote share fell in June's election, it had a "good platform" from which to move forward.
"What we now need to do is start winning again. We have been through a very difficult period post-coalition. Winning in local government, winning in national government, that is the next step.
"When the people see us getting back in that way, the positives about our party will really take off."
'Middle of the road'
He suggested his party was the natural home for voters dismayed not only by the Tories' and Labour's support for Brexit but by what he said was the growing polarisation of the political system.
"What we offer is a package that is moderate, sensible, and middle of the road. I think people will actually be craving a government by people who have the combination of experience and idealism which we do have."
Challenged over whether 'middle of the road' sounded dull and uninspiring, he replied: "Common sense is a virtue given the kind of extremes and, frankly, rather infantile behaviour we are getting, the stuff we are seeing from Boris Johnson and his colleagues makes people despair of politicians."
Although he admitted new policy development was at an early stage, he said his aim was to tackle inter-generational inequalities in a variety of ways, using the resources of the government and the private sector to "break the mould" on housing and come up with more imaginative solutions to house building.
He said he wanted to examine how a new approach to the "transfer of wealth" could generate money to be spent on post-16 education, whether to support future graduates or those going into further education.
"I want the party to be a source of bold new ideas... the ideas are at an early stage. We have got the framework. I think they will be radical and they will be popular."
On tuition fees, he defended the basic principles of the current system - which the Lib Dems helped design while in government - but said the way it was working in practice needed reform.
"There are clearly things that are not working - the interest rate system is unsatisfactory... and most seriously of all they have abolished grants for maintenance which is absolutely critical for people from poor backgrounds.
"They have taken that away. That has probably done more to add to student debt than tuition fees."
Speaking at the Bournemouth conference, education spokeswoman Layla Moran said talk of Sir Vince becoming PM was "good fun" but the party needed to focus on adopting "distinctive positions" not dreaming of power.
"It's not just the leadership, there is a portion of the wider party that still kind of believes this too, that somehow we are going to go back into government at any moment," she said."And I think we need to kind of accept we're not."