ST. PAUL, Minn. (AP) — Republican candidate Kurt Zellers said Wednesday he had signed a conservative group’s pledge that rules out any net tax increases and most new fees as budget options if he becomes Minnesota governor, a position he reinforces in a television ad ahead of next month’s wide-open GOP primary.

The retiring legislator, who’s also a former House speaker, said he wanted to make clear that he won’t ask taxpayers to pony up more money. None of Zellers’ rivals in the Aug. 12 GOP primary have signed the Americans for Tax Reform document, according to the group founded by anti-tax advocate Grover Norquist. The primary winner faces Democratic Gov. Mark Dayton this fall.

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Zellers said at a news conference that taxes had risen too much the past four years — even if they were targeted at high-income earners or smokers.

“Voters need to know that in my case that won’t be — in any way — the way we’re going to balance the budget or increase spending,” Zellers said.

The pledge binds its signers to a commitment to oppose and, if necessary, veto “any and all efforts to increase taxes.” The pledge allows for “user fees” were the revenues are specifically dedicated to a service; fees where excess money flows into a general treasury violate the terms. Signers can pursue policy change that increases a tax in one area so long as corresponding reductions are enacted, too.

Zellers has signed it previously as a state legislator.

To gain the GOP nod, Zellers must overcome Scott Honour, former Rep. Marty Seifert and Hennepin County Commissioner Jeff Johnson in the state Republican Party’s first competitive primary for governor in two decades.

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In a television ad that will air on cable stations starting Wednesday in select markets, Zellers refers to his promise to hold the line on taxes and says he’s the only candidate with “the guts to put it in writing.”

Johnson, who has the Republican Party’s endorsement in the race, said his record speaks for itself.

“In six years in the House and five years as county commissioner, I’ve never voted for a tax increase,” Johnson said in a written statement. “As governor, my philosophy will not change.”

The others in the race didn’t immediately respond to requests for comment or said they needed more time. Dayton’s campaign spokesman didn’t immediately respond either.

Minnesota’s last Republican governor, Tim Pawlenty, signed a tax pledge during his first campaign. But he declined to renew it during his successful re-election run, calling that pledge and others pursued by interest groups a distraction.

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