TORONTO - Former premier Mike Harris is stepping up his campaign to make Tim Hudak the next leader of the Ontario Progressive Conservatives, as all four candidates race to pick up support before party members head to the polls in late June.

In a video obtained by The Canadian Press, Harris urges his fellow Tories to vote for Hudak, saying he's their best shot at beating Liberal Premier Dalton McGuinty in the 2011 provincial election.

"(I) had the corner office at Queen's Park for seven years," Harris says as he faces the camera directly.

"I know the responsibility and the hard work that goes with that job, and I know Tim Hudak."

Hudak is a "champion" for hard work, lower taxes and middle-class families, and can "energize and unite" the party, he adds.

"And you know, whenever we have offered a clear, conservative plan that makes sense for our hard-working, middle-class families, we have been rewarded by the voters," he says.

The message from Harris, who has been working behind the scenes for the Niagara-area politician who served in his cabinet, will be emailed to party members Tuesday and posted on Hudak's campaign website.

It's part of larger push ahead of the June 21 and 25 votes, which will include door-to-door canvassing and a conference call with organizers to be hosted by Harris and federal Justice Minister Rob Nicholson, said Jeremy Adams, a spokesman for Hudak.

The fact Harris has left the sidelines to endorse Hudak says a lot about his potential to lead the party, Adams said.

"Within the Conservative Party, Mike Harris is by far the most popular figure, period," he said.

"He's a rallying point for Conservatives who can look through this leadership election to a united and energized party that we have not had for a number of years."

Harris has lent his star power to leadership campaigns before. He supported Belinda Stronach's 2004 bid for the leadership of the federal Conservative Party, but she lost to Stephen Harper and defected to the Liberals the following year.

The video also speaks volumes about the contest itself, which has made a surprising turn from coronation to horse race, said politics professor Bryan Evans of Toronto's Ryerson University.

"What I think (the video) does tell you is in fact that they recognize that Tim Hudak is in a contest, and his primary opponent is in fact Christine Elliott," he said.

Elliott, a Whitby lawyer who is married to federal Finance Minister Jim Flaherty, shrugged off suggestions Monday that Harris's influence could sap support from the other candidates.

"Some people want to go back and redo old campaigns from the past," she said.

"I don't agree with that. I think that the way that we win in the next election is to take the good parts from the past ... but we need to look to the future."

Sandra Buckler, spokeswoman for two-time leadership hopeful Frank Klees, said she doesn't think the video will be well-received, even though Harris is well-respected in Tory circles.

"I don't think our party members will take kindly to the concept that a former premier will `make' anyone the next premier," she said in an email.

"That's reserved for the members themselves and they'll base their decision on who they believe is best qualified."

A spokesman for Randy Hillier -- largely considered to be the most right-wing candidate in the race -- said it's "fantastic" that Harris has come out of political hibernation to get involved in the race.

But Hillier is more concerned about shaping the policy debate, not showing off big-name supporters, said Nick Kadysh.

"We haven't focused on that because that's not where we think the focus of the leadership race should be," he said. "It should be on the future of the PC Party."

Hudak has been labelled the heir apparent to Harris and his successful Common Sense Revolution platform, which propelled the party to power in 1995.

Harris, a hero to the party's most devout conservatives, cut taxes and slashed spending in Ontario, including a 22 per cent reduction in welfare rates.

His government's controversial agenda sparked angry labour unrest and widespread protests that culminated in a violent clash between police and anti-poverty activists on the front lawn of the provincial legislature in 2000.

Hudak has dismissed suggestions that he wants the party to return to its Common Sense days, despite his strong ties to that era and the support he's receiving from many of the architects of that right-wing agenda.

The party will vote using ballots that rank the candidates in order of preference. Ballot boxes will be sealed and sent to the convention, where a new leader will be announced June 27.