Gordon Brown, David Cameron and Nick Clegg last night made impassioned pitches to voters as they faced-off in the final televised debate of the General Election campaign.

The party leaders clashed over immigration and the economy in the 90-minute BBC debate at the University of Birmingham.

Mr Brown tried to draw a line under Wednesday's row when he branded a pensioner "bigoted" after she raised concerns over immigration with him, issuing a plea to voters to judge him on his economic competence and not his personality.

"There is a lot to this job and, as you saw yesterday, I don't get all of it right," he said. "But I do know how to run the economy, in good times and in bad."

Mr Cameron said: "If you vote Labour, you get more of the same. If you vote Liberal Democrat, it is uncertainty."

Only an outright Tory victory could deliver "a clean break, taking our country in the right direction and bringing the change we need".

And Mr Clegg urged voters not to be frightened of voting for "something really different".

"This is your election, this is your country," Mr Clegg said. "When you go to vote next week, choose the future you really want."

Mr Brown acknowledged that in eight days' time, Conservatives could be in power - perhaps with Liberal Democrat support - after 13 years of Labour rule.

And he said: "I don't like having to do this, but I have got to tell you that things are too important to be left to risky policies under these two people. They are not ready for government, because they have not thought through their policies."

Mr Brown spoke speedily and rattled through the government's policies and his own concerns, Tory leader David Cameron sounded predictably at ease with the issue and it was left to the Liberal Democrat leader Nick Clegg first to seem to deny his party's policy of an amnesty for illegal immigrants, then flounder while explaining it.

All three leaders were put through their paces, first on the economy then on issues from benefit scroungers to the affordability of housing to the future of education.

And in his perhaps final 90 minutes to undo the damage he did on Wednesday, Mr Brown - blighted by his nervous grin - fulfilled Labour election strategist Lord Mandelson's ambition that he should be seen as a workhorse rather than a "show pony".

Mr Cameron gave his most assured performance yet, looking far more relaxed and comfortably addressing viewers straight down the camera lens, addressing Mr Brown frequently as Prime Minister - rather than Gordon or Gordon Brown, as he had done the previous two weeks.

It was a tactic presumably designed to highlight the fact that Mr Brown's party has been in power for the last 13 years, and pay due deference to his office, eschewing the rather showy "if I was your Prime Minister" formula the Conservative leader deployed last week.

Mr Clegg looked less at ease than during any of the previous contests, not just over immigration but on a range of issues where he tried to cut across the other two leaders and seemed sometimes at pains to agree with every questioner.

But if his performance last night was somewhat lacklustre, he has undoubtedly been the big winner of the first series of televised showdowns which look set to become a fixture of British election campaigns.