The former British home secretary and leading member of Britain's main opposition Conservative party, revealed his ambitions a day after disgruntled Tory members of parliament ousted Iain Duncan Smith as leader.
Howard, 62, the party's spokesman on finance issues, threw his hat into the ring less than 24 hours after Duncan Smith's demise.
Political observers say he is easily the runaway favourite to take up the helm of the troubled Tories.
"I am announcing today that I am a candidate for the leadership of the Conservative Party," said Howard to a group of reporters and supporters at the hip Saatchi art gallery, across the River Thames from the British parliament.
Duncan Smith - described as
"I will lead this party from its centre," he said, adding that the Tories need to put "ancient feuds" in the past and "build afresh".
The Conservative Party, which spawned British political heavyweights such as Winston Churchill and Margaret Thatcher in the last century, has been defeated twice in succession by Prime Minister Tony Blair's New Labour party.
The Tories look destined for another drubbing in polls, which need not be called until mid-2006.
But as the Conservatives sought a leader capable of mounting an effective challenge to Blair, Howard insisted that the Tories could overturn Labour's huge majority.
In an interview in the Friday edition of Britain's biggest-selling daily newspaper, The Sun, he said: "Of course we can turn things around at the next election.
"On one night in 1997, our majority disappeared. But what happened that one night can just as easily happen the other way in one night."
Howard told the paper he was looking forward to the challenge of taking on Blair: "I'm up for it. I'm very excited. I think this is the turning point.
"But I will do things my way," he insisted. "I expect everyone in the party to play their part in this team."
Duncan Smith was accused of being too ineffectual and failing to capitalise on Blair's falling popularity in the wake of the Iraq war.
Weeks of speculation and backroom intrigue ended Wednesday when the 165 Conservative members of the House of Commons voted 90-75 to reject Duncan Smith, who has headed the party for less than two years.
"On one night in 1997, our majority disappeared. But what happened that one night can just as easily happen the other way in one night"
The Guardian newspaper called Duncan Smith "the leader who was never meant to be". He was "simply too ineffectual, too weak on television, too devoid of charisma, to make a fist of opposition," wrote columnist Jonathan Freedland.
No sooner had Duncan Smith got the boot than other Conservatives raced to present a public image of unity.
Heavyweights like David Davis, Michael Ancram, Oliver Letwin and Michael Portillo took turns to announce that they would not challenge Howard.
Duncan Smith, a former British army officer and businessman with no experience in government, was a backbench legislator when he won the leadership after the Tories' second straight election loss to Labour in 2001.
Speculation about his future haunted the Conservatives' annual conference in October, where the party unveiled a platform calling for better old age pensions, free university tuition and more police on the streets.
Howard said Thursday that he would uphold that platform, which he helped build, and pitch its contents to voters as "realistic alternatives" to Blair and Labour.
On foreign policy, he said the Conservatives would be internationalist, and that if it raised concerns about the European Union, it would not be because Tories were "little Englanders".
The deadline for leadership candidates to step forward is next Thursday, with the first round of voting to follow on 11 November if Howard is not the sole aspirant.