The 2006 gubernatorial election is still almost two years away, but several potential Republican candidates are positioning themselves to mount a challenge to Gov. Jim Doyle.

The short list of possible candidates centers on Milwaukee County Executive Scott Walker, U.S. Rep. Mark Green and State Assembly Speaker John Gard, although none have officially announced their candidacies.

Walker, in particular, has furiously sought to stake out a spot on the property-tax debate, leading many to say he is preparing to run.

The Milwaukee County executive mailed his own property-tax bill to Doyle’s office — and urged constituents to do the same — as part of his “We Need the Freeze” campaign aimed at preventing increases in property-tax levies.

Citing statistics from the Tax Foundation showing Wisconsin has the nation’s 10th-highest per capita property taxes, Walker has repeatedly asked Doyle to sign a Property Tax Levy Freeze. The governor vetoed such legislation last session.

Walker struck again after Doyle expressed support for the repeal of the state’s Qualified Economic Offer Law in his State of the State address. The Wisconsin Education Association Council, a Doyle ally, has long opposed the QEO for holding down teachers’ salaries. However, Walker claims repealing the law would lead to more increases in property taxes.

Long rumored to be a leading candidate for governor, Green indicated he is giving serious thought to a gubernatorial campaign in an e-mail to statewide Republican leaders last week

“I hope you’ll join me in working to take back the governor’s office,” Green, who represents Wisconsin’s northeastern portion in Congress, wrote. “Let’s aim higher, toward a brighter future for our state.”

Like Walker, Green figures to target Doyle’s stance on taxes, including the property-tax freeze and Taxpayer Bill of Rights.

“The only ‘leadership’ we see [Doyle] demonstrate is that he is always the first to say ‘no,'” Green wrote. “‘No’ to freezing property taxes, ‘no’ to putting controls on government spending, ‘no’ to requiring photo IDs for voting, ‘no’ to education reform, ‘no’ to protecting the sanctity of marriage … and the list goes on and on.”

Gard has kept a lower profile than Walker or Green, keeping quiet on whether a gubernatorial campaign is in the works. His office was unavailable for comment.

But Democratic colleagues of Gard’s have accused the speaker of keeping an eye toward the East Wing of the Capitol when making policy decisions. Rep. Mark Pocan, D-Madison, said he has observed Gard’s political ambitions.

“John Gard is clearly running for governor or Congress — or the position of God, if it was open,” said Pocan, one of Gard’s more vocal critics in the Assembly. “He’s an extremely ambitious man.”

Others say the sale of Christmas ornaments late last year by Gard’s wife, former state legislator Cate Zeuske, was really an effort to aid Gard’s campaign. Zeuske plans to sell the ornaments, which generated money for the Capitol’s restoration fund, again next year.

Regardless of who runs, Republicans may face a similar quandary: the platform they are likely to campaign on — fiscal responsibility and government accountability — is not the weakness for Doyle that some thought it would be.

“Doyle can certainly make that argument (of fiscal responsibility),” UW political science professor Dennis Dresang said. “The only thing he would have to explain would be local property taxes. But he could remind people that’s not just his decision, but also the Republican legislature and local governments’.”

Dresang said it is too early to handicap the potential race between the three Republicans, saying only that Green may have a financial advantage due to a law allowing him to convert funds from his congressional campaign to a gubernatorial campaign.

Perhaps the most intriguing 2006 match-up would pit Doyle against former Wisconsin Gov. Tommy Thompson.

Thompson enjoyed widespread support during his time in the Capitol, but Doyle would be able to blame him for the state’s financial woes, Dresang said.

However, according to his brother, Ed Thompson, the departing Health and Human Services Secretary’s status to return to the post he held for 14 years is up in the air.

“I have no idea what he’ll do,” Thompson said.

For his part, Ed said he was leaning strongly toward not reprising his 2002 Libertarian campaign for governor in 2006, admitting he was unlikely to improve on his 10-percent showing as a third-party candidate.