Tim Farron has refused to rule out standing for the leadership of his party, in an interview published ahead of the Liberal Democrat conference.
Farron, who is on the left of the party, has often been tipped as a future successor to Mr Clegg. The MP also called for a major rethink of the government's economic policy ahead of his party's conference.
The Liberal Democrat president told The House magazine: "I'm not saying I would never do it but I'm always suspicious of people who are overly personally ambitious because you kind of think what's the point really?
"But if there's a job to be done it will depend on what the lie of the land is and then ... I certainly wouldn't rule it out."
Farron called for tax cuts for the poor and the use of quantitative easing to boost social housing construction instead of "squandering cash on wealthy people".
Tim Farron says there's nothing wrong with Lib Dems talking to Labour
And just as Mr Clegg attempted to draw a line under the row with a video apology, Farron said that the Lib Dems would have to return to the issue of tuition fees at the next election.
Party activists will gather in Brighton on Saturday for a conference which will see the Lib Dems attempt to differentiate themselves from their Tory coalition colleagues under the banner Fairer Tax in Tough Times.
The party believes its key fiscal policy of increasing the income tax threshold to £10,000 is one of the coalition's more popular ideas.
But Mr Farron said there was a need to do more, emphasising the need for a stimulus package to secure growth.
In his Budget this year George Osborne announced a cut in the top rate of income tax from 50p to 45p, but Mr Farron dismissed the impact of such measures.
He told The House magazine: "The answer is more demand and that means more tax cuts for the least well off, not squandering cash on wealthy people who will then go and save it or spend it abroad.
"And you have to find ways of releasing money into the economy. I want us to be much more intelligent about quantitative easing.
"Why don't we just do it through social housing bonds? Just giving it to the banks is untargeted and goes into the hands of the wealthy really.
"If it's about build, build, build houses for families, for young people, people at the lower end of the property scale, you will do a wonderfully important thing anyway and you will help kickstart the economy."
Mr Clegg's decision to make a public apology for making a pledge he could not keep to oppose a rise in tuition fees has been lampooned in a video which has gone viral on the internet.
Mr Farron insisted that the Lib Dems should return to the issue in their election manifesto.
He said: "A line in the manifesto about what we will do about fees is obviously something we should definitely be looking at.
"We should be looking to ensure the higher education funding system is fair - and not just fair but seen to be fair.
"Perceptions are everything, so we need to do something perhaps to address that.
"I appreciate there's not tonnes of cash but something around a graduate tax, a graduate contribution system where we rid ourselves of the nomenclature of loans and of debt would be something I would like to do, but I'm not in the position of being able to reveal the manifesto yet.
"The Tories wouldn't have a word with tax in it. But if you have to pay something on a regular basis, that's what it is.
"So you may as well make it fair and you may as well divorce it from the whole notion of debt which we ought to have done.
"There will not be an absence of tuition fees in the next party manifesto, I'm certain of that."
Mr Farron also defended Lib Dems for talking to Labour, saying the two parties had a shared history and the coalition with the Tories was a matter of the electoral "arithmetic" rather than ideology.
Business Secretary Vince Cable has admitted exchanging text messages with Labour leader Ed Miliband.
Mr Farron said: "Why can't we talk to each other? There is a progressive history between us, we come broadly from the same stable a century or so ago, so by talking to Labour we do have people who are pro-constitutional reform, some people who are genuinely positive about the environment ... and many of them do understand that their leadership has been very stupid in their position towards us over the last two-and-a-half years."