UK election: Main party leaders

PRIME MINISTER TONY BLAIR

For the 51-year-old Blair, the youthful looks and public admiration that swept him to power in 1997 are long gone, the latter washed away by widespread opposition to his decision to join the US-led invasion of Iraq.

But Blair is determined to win a third successive term -- a first for a Labour leader -- and opinion polls suggest he will succeed. Following medical treatment to regulate his heartbeat last year, Blair said he would not seek a fourth term.

After backing US President George W. Bush over Iraq, and with no evidence of the weapons of mass destruction the two leaders said Saddam Hussein possessed, Blair's public trust ratings have slumped.

It is a far cry from 2001 when he led his party to its second successive landslide election win. At that stage the Scottish-born barrister could do no wrong.

Married to high-profile lawyer Cherie and the father of four children, Labour's youngest leader -- he took office at the age of 43 -- did not come from a typical party working-class background and has often been viewed with suspicion by left-wingers.

Blair became party leader in 1994 after predecessor John Smith died of a heart attack and promptly set about severing its socialist roots and reshaping it to appeal to middle-class England, preserve of the Conservatives who had held power since 1979.

In 1997, he was rewarded with a huge parliamentary majority.

MICHAEL HOWARD, CONSERVATIVE PARTY LEADER

Howard, 63, son of Jewish immigrants from Romania, is an astute, Cambridge University-educated barrister with a forensic mind who has proved a match for Blair in parliamentary debates.

But he is still linked to Conservative governments of the late 1980s and 1990s. Then, he courted controversy as a hardliner and launched the punitive poll tax which sparked nationwide protests and sped the demise of Margaret Thatcher.

Hoping to capitalise on a slump in public trust in Blair, Howard trumpets honesty and honour as key credentials.

But he has struggled to shake off being described as having "something of the night about him" by a party colleague during a dispute in 1997. Cartoonists delight in depicting him as Count Dracula.

Howard is vehemently against Britain joining Europe's single currency and opposes the new European Union constitution.

His election campaign got off to a strong start with initiatives to curb immigration and reform public services that put Blair on the back foot.

But it ran into trouble last week when he sacked a party deputy chairman who said the Conservatives would cut public spending deeper than they have said.

CHARLES KENNEDY, LIBERAL DEMOCRAT LEADER

Kennedy, 45, son of a farmer from Scotland's remote Highlands, is Britain's most popular mainstream party leader.

Opposition to the war in Iraq proved a vote winner and support for his Liberal Democrats surged last year to its highest level since the party was formed in 1988.

The ginger-haired Scot was Britain's youngest politician when he entered parliament in 1983 for the Liberal Democrats' predecessor party. Since taking over as leader in 1999, he has steered it away from previous close ties with Labour.

But critics say "Chat-show Charlie", as he has been dubbed by the media, lacks the stamina or gravitas needed for political leadership.

A self-confessed bon viveur who had no qualms about taking part in satirical television quiz shows, Kennedy has the golden electoral benefit that his wife is just given birth to their first baby.

CHANCELLOR GORDON BROWN

Brown, 54, remains the man most likely to succeed Blair as prime minister but the brooding Scot has waited a long time for the top job in British politics.

Blair and Brown both entered parliament in 1983 and rapidly rose through the ranks of a Labour Party struggling to reinvent itself. Brown was always the senior in the partnership.

Labour folklore has it, however, that when party boss John Smith died in 1994, Brown agreed to give Blair a clear run at the leadership on the understanding he would one day take over and in the meantime be given unprecedented control of domestic policy as finance minister.

Blair's allies deny any such deal. Brown's say it happened and should have been honoured by now. Their tempestuous relationship hit a new low earlier this year when Blair stripped Brown of his traditional role heading election strategy.

Rumours are rife that Blair will move him from the Treasury if Labour wins the election comfortably, but most party insiders say that is unlikely as it would at a stroke free the powerful Brown to start actively lobbying against his boss.

For eight years as chancellor, Brown has delivered solid economic growth. That remains his party's strongest card.

- REUTERS