Lib Dem leader Charles Kennedy has attacked Britain's voting system as "perverse", and vowed not to form a coalition with Labour.
Mr Kennedy told a BBC Question Time special his position in a hung parliament would not change even if Tony Blair was no longer leader.
And he defended his presentation of Lib Dem taxation policies.
The Lib Dem leader also repeated his belief that UK troops should withdraw from Iraq at the end of the year.
He said this should apply even if the Iraqi government requests them to stay, although he did say that any request for British troops to take part in a UN peacekeeping mission should be considered.
Mr Kennedy answered a simple "no", when asked whether he would join a coalition.
"No, we wouldn't support Tony Blair. If you have a parliament where there's no overall majority next time, a government's got to be formed.
"That party, which has the first opportunity to form a government, is going to have to conduct itself in Parliament by taking account of opposition parties' view points - also dissenting voices in its own party.
"That's a much healthier way to proceed that what we have had over the last four years in particular which is a government with a big majority riding rough-shod not just over opposition opinions but over the substantial opinions of its own members of Parliament."