SUPPORT was slipping away fast from long-time Tory leadership frontrunner David Davis last night as the party's "beauty parade" conference ended in Blackpool.

Two backbenchers who were close to endorsing the Shadow Home Secretary to succeed Michael Howard changed their minds following his lacklustre speech a day earlier.

James Gray, the North Wiltshire MP, said he was switching to David Cameron, while Forest of Dean MP Mark Harper was expected to endorse Liam Fox early today.

Mr Gray - who had described himself as 70 per cent certain to back Mr Davis - now said of Mr Cameron: "He has a certain something about him, a 'je ne sais quoi'."

Meanwhile, two Davis big-hitters, industry spokesman David Willetts and former education spokesman Damien Green, were also believed to be close to jumping ship.

The loss of support suggested Mr Davis' poor performance had blown the contest wide open in the run-up to the first ballot among Conservative MPs on October 18.

But a bullish Mr Davis said he was still "odds-on favourite", insisting his list of 66 declared supporters among the 198 Tory MPs was rock-solid.

If correct, that would put him just one vote shy of the 67 that would guarantee a place in the run-off of the top two candidates among grassroots members.

However, there was no doubt the momentum is now with the three candidates who all spoke impressively from the platform this week - Mr Cameron, Dr Fox and Ken Clarke.

Rightwinger Dr Fox claimed 30 promises and arch-moderniser Mr Cameron at least 20, including Shadow Transport Secretary Alan Duncan, who endorsed him yesterday morning.

Mr Howard, who formally resigned the leadership yesterday, also gave subtle backing to Mr Cameron in an interview in which he said "one more heave" would not win back power.

The phrase was an exact echo of the words used by Mr Cameron in his conference speech, in which he urged the Tory faithful to embrace radical change.

In his close-of-conference speech, Mr Howard was careful not to endorse any of the five candidates, preferring instead to make plea for unity whoever is the winner.

Mr Howard said: "Of course we need discussion and debate. But let's not be offensive about each other.

"Let's not run down our party. Let's show we can elect a new leader without bitterness and backbiting."

In an emotional send-off in which he reminisced about the 35 years since he first spoke to a Tory conference, Mr Howard also confessed to coming up short as leader.

He said: "Let's be honest with each other - we didn't even come close to winning. My best turned out to be not good enough."

Following the first leadership ballot on October 18, there will be further votes until the field is whittled down to two candidates.

The two finalists will then begin intensive campaigning to woo the estimated 300,000 Tory members, with result of their deciding vote due on December 6.