Donald Trump's early surge toward the Republican presidential nomination is dividing GOP loyalists in Minnesota and prompting the billionaire's many party critics to talk openly about taking steps they once thought impossible.

"No. I will not vote for him," said Charlie Weaver, a business lobbyist and onetime top aide to former Gov. Tim Pawlenty.

"I'm not quite sure what I'm going to do at this point," said Weaver, adding that he could not vote for Democratic front-runner Hillary Clinton.

Republicans at the Minnesota caucuses handed Trump his only third-place finish, living up to the state's history of going its own way politically. Unfortunately for the Republicans who voted for Sens. Marco Rubio of Florida or Ted Cruz of Texas, they still stand a good chance of getting stuck with Trump.

That outcome would likely complicate the Minnesota GOP's efforts to hold its state House majority and endanger its hopes of winning control of the state Senate.

For many Minnesota Republicans, their worries go further. They worry about a Trump-run White House.

"Many of us fear, what will he do then?" said Rep. Steve Drazkowski, R-Mazeppa, who backs Cruz. "I mean he is basically a political chameleon who is very willing and able to change his stripes in order to accomplish his goals."

As Trump racks up wins across the country, his success threatens to unravel the GOP. Some of his GOP critics want a brokered convention to block him. But that maneuver would alienate millions of Trump's supporters, many of whom have little allegiance to the party.

"It's not Washington's party, or the insiders' party, or Karl Rove's party," said Sen. Julianne Ortman, R-Chanhassen, the highest-ranking GOP elected official in Minnesota to back Trump so far. "It's the voters' party, and the issues important to voters are jobs, the economy and national security. Donald Trump is addressing these issues in a way that resonates with ­voters."

Ortman, a 14-year state Senate veteran, is not running for re-election.

Barbara Mura-Sutter, a GOP activist from Bloomington and 2014 legislative candidate, still has qualms about Trump after initially supporting Wisconsin Gov. Scott Walker and then Carly Fiorina. But she sees it as a huge mistake for GOP power brokers to try to block Trump at the convention.

"That's just abhorrent," Mura-Sutter said.

Mark Drake, who previously worked for Pawlenty, former Sen. Norm Coleman and the GOP locally and nationally, cited a number of Trump's more outrageous plans or actions for why many in the GOP are so uneasy: His call for a ban on all Muslims entering the U.S.; his ridicule of Sen. John McCain for having been a POW; his initial refusal to denounce white supremacist David Duke and the Ku Klux Klan.

Drake won't vote for Clinton, but said he could see some Republicans doing so. Weaver would be ready to vote for a third-party candidate, even though he thinks that would likely help ­Clinton.

"I'm worried less about my party than I am about my country," Weaver said.

Not all of Trump's GOP foes will shun him if he is nominated. Minnesota's three Republican members of Congress — Reps. John Kline, Erik Paulsen and Tom Emmer — all told the Star Tribune they'd support Trump if he becomes the standard-bearer.

"I'll support the nominee," said Hennepin County Commissioner Jeff Johnson, the GOP candidate for governor in 2014 and Rubio's Minnesota campaign chairman. "But it would be with different levels of enthusiasm depending on the candidate. With Trump it would mean voting for him but not doing a lot more than that."

There's little doubt Democrats would try to attach every one of Trump's outrageous statements to GOP candidates up and down the ballot.

"He's the face of their party if he's the nominee," said Susie Merthan, spokeswoman for Alliance for a Better Minnesota, a political action committee that works to elect DFLers. "Trump wants to take us backward and I think that's where we're going to come at it from."

Annette Meeks, a longtime Republican operative who ran for lieutenant governor in 2010, can't stand Trump. She thinks he would make it hard for her party to hold onto Kline's largely suburban Second Congressional District. A handful of Republicans still hold state House and Senate seats in suburban areas that have trended toward the DFL in recent years.

"He's a big drag in suburban, affluent districts," said Meeks, who leads the conservative Freedom Foundation of Minnesota. But she believes it's possible that he could help GOP candidates in some rural and economically depressed areas.

Why the disdain for Trump? Weaver called him "a self-centered bully." Coleman called him a fraud, a misogynist, and frightening. Former U.S. Rep. Vin Weber, a powerful Washington lobbyist, called Trump's proposed ban on Muslim immigrants "deeply, morally offensive."

Recently, broadcasting magnate Stanley Hubbard, a frequent political donor who favors Republicans, donated $10,000 to a political action committee trying to derail Trump.

"I think only people of the highest integrity should be president," Hubbard said. Would he support Trump as nominee? Hubbard initially said yes: "You play by the rules of the game, and if he wins the game you have to back him."

Later, his tone shifted.

"I've thought before that if Trump is the nominee, I'd support him," Hubbard said. "I'm not so sure. It's too early to say for sure."

Staff writer Allison Sherry contributed to this report.

Patrick Condon • 651-925-5049