LANSING, Mich. (AP) — Ten Republicans filed petitions to run for Michigan governor by Tuesday’s deadline, a record number in recent history, creating a huge field for a primary electorate that will decide who challenges Democrat Gretchen Whitmer.

Candidates include ex-Detroit Police Chief James Craig, self-funding wealthy suburban businessmen Perry Johnson and Kevin Rinke, chiropractor Garrett Soldano and conservative former TV host Tudor Dixon, who are both from western Michigan.

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The lineup for the August primary may shrink if election officials find problems with the 15,000 to 30,000 signatures that were submitted by each campaign, which can be flagged by rivals who must file challenges no later than April 26. As of now, however, the field dwarfs past ones.

Whitmer won a three-person primary in 2018 on her way to the governorship of the swing state. Her predecessor, Republican Rick Snyder, emerged from a five-way primary in 2010.

A 10-candidate gubernatorial primary would be the largest in recent history, said state archivist Mark Harvey, who noted the difficulty of checking back to statehood 185 years ago.

Others vying for the GOP nomination are state police Capt. Michael Brown, real estate broker Ryan Kelley, pastor Ralph Rebandt, businesswoman Donna Brandenburg and financial adviser Michael Markey Jr.

Whitmer is seen as vulnerable in November, because voters tend to back the party opposite the president in midterms and they are facing high inflation as the economy rebounds from the pandemic. Yet her Republican challengers, who have criticized her past COVID-19 restrictions, are all political newcomers who are untested.

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Polling has shown Craig leading, and he declared himself the candidate to beat while turning in petitions. But Richard Czuba, a pollster who has long tracked Michigan politics, said it is a wide-open race.

“The next couple months we’re going to increasingly see the Republican field move farther to the right and start beating the hell out of each other,” he said, suggesting independent voters will be turned off. “That’s a huge advantage that’s been undercounted for Gov. Whitmer.”

Still, he expects a close race in the fall, predicting that GOP voters will unite behind the eventual nominee.

No first-term governor has lost in 60 years. But Whitmer is the first incumbent in 48 years to seek reelection while her party controls the White House.

“I don’t think anybody knows where this is going to go yet,” Czuba said. “We know that the power of an incumbent Michigan governor is very strong. We’re going to see if it can withstand a national tide which might emerge for the Republicans.”

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