Deputy Prime Minister Nick Clegg said he hoped voters in the Eastleigh by-election would be able to look past the criminal behaviour which led to Chris Huhne's resignation and instead focus on the Liberal Democrats' policies and record.
Clegg said he was "shocked" by disgraced ex-Cabinet minister Huhne's conduct, which resulted in him quitting as an MP after pleading guilty to perverting the course of justice.
The by-election contest will see Clegg's Lib Dems engage in a full-blooded fight with their coalition partners the Conservatives, who hope to regain a seat they lost in 1994.
Clegg said Huhne's criminal conduct and the trial of his ex-wife Vicky Pryce would "undeniably" be an issue in the campaign but voters would be able to separate the "courtroom drama" from the political issues.
He told Sky News' Murnaghan programme: "As I have said before, I was very shocked and sad to see what happened and to see that his whole family has been engulfed in this in a very public way.
"I think you have to have a heart of stone not to think that is a pretty shocking and sad thing."
Clegg said he had taken Huhne's assurances "at face value" and was only informed about his change of plea the night before he admitted the offence.
He said: "At the end of the day Chris needs to speak for himself, needs to answer himself and needs to make amends for what has happened and what he's done.
"I don't actually think, at the end of the day, when people come to vote in Eastleigh on February 28, whilst they may have strong feelings one way or another about Chris Huhne, I've heard lots of people say they don't like what's happening in the court, but they actually think that what he did as a local MP was the model of a Liberal Democrat working hard for the local community.
"I think most people will be able to separate the courtroom drama, which at the end of the day is a very private drama being played out in public by divisions within a family, I don't think people will make their judgment on that about who they want to represent them in Parliament for the future.
"I think what people will care about is what does it mean for jobs in the local area, what does it mean for housing in the local area, what does it mean for fair taxes in the local area.
"Those are they kind of things we are going to be campaigning on between now and by-election day."
Clegg said the coalition would remain strong despite the prospect of a bruising contest with the Conservatives on the doorstep in the Hampshire seat.
He even suggested Prime Minister David Cameron could end up in the constituency at the same time as him.
"We may end up there at the same time, that would be a change from sitting around the same table in Whitehall to actually campaigning in different streets in Eastleigh."
He insisted it a "great opportunity" for the Lib Dems to highlight their achievements and that it was right not to agree a truce with the Tories over the seat.
"I personally am always against any kind of whiff of stitch-ups because it is important to give people a choice," said.
Mike Thornton, a parish and borough councillor since 2007, was selected to fight the seat for the Lib Dems in a hustings last night.
He will be up against Tory candidate Maria Hutchings, a staunch eurosceptic and opponent of David Cameron's gay marriage reforms which have split the party. She previously stood against Huhne in 2010, losing out by 3,864 votes.
According to a poll released last night, the Lib Dems remain in front in Eastleigh spelling potential defeat for the Prime Minister.
The Survation poll for The Mail on Sunday put the Lib Dems on 36%, ahead of the Tories on 33%. The poll also put the UK Independence Party on 16%, ahead of Labour on 13%.
In a sign of the way Huhne's conduct will cast a shadow over the campaign, Tory Defence Secretary Philip Hammond said the Conservatives were fielding a candidate "people will be able to trust".
Survation polled 504 people in Eastleigh by telephone on Thursday.