Donald Trump is enduring one of the worst weeks of his campaign. Is it a bump or a turning point?

Reporting from Green Bay, Wis. —  After months of dominating the Republican race, Donald Trump has endured one of his worst weeks since launching his presidential bid, and while he remains the GOP front-runner, his struggles have underscored his weaknesses and increased the possibility that he might fall short of seizing the nomination.

The bad news piled up quickly for Trump: his campaign manager charged with misdemeanor battery on suspicion of grabbing a female reporter’s arm, a series of interviews with conservative talk radio hosts who pummeled him, a highly regarded poll showing him trailing badly in advance of Wisconsin’s primary next week, and finally Wednesday’s fracas over his stand on abortion.

All of those developments deepened existing doubts about Trump. Many Republican strategists worry about his staggering level of unpopularity with female voters, which were highlighted by the battery charge against campaign manager Corey Lewandowski and Trump’s comment suggesting women should face “some sort of punishment” for getting abortions if the procedure is made illegal.

Those sorts of stumbles, as well as Trump’s calls to talk show hosts whose opposition to him he seemed unaware of, all raised questions about whether he is capable of building and running a campaign operation that can win a general election, experienced political operatives said.

“You’re seeing a campaign that’s making it up as they go along every day. That’s deadly,” said John Brabender, who was chief strategist for former Sen. Rick Santorum’s campaign and is now neutral on the race.

Trump’s “renegade campaign” and defiance of political norms “served them fine in the early phases,” Brabender said. Now, however, it’s “hurting Trump a great deal.”

The problems come at a contradictory point in the campaign for Trump. He has defeated one rival after another. But he continues to draw support from only a minority of Republican voters. That contrasts with front-runners in previous presidential contests who had begun pulling away from rivals by this point in their campaigns.

Of course, Trump has proved skeptics wrong time and again, demonstrating a hold on his supporters that has defied conventional political judgment.

Part of what may make this rough patch different is the Wisconsin polling, which has added something beyond anecdote to the forecasting.

Based simply on its demographics — with a large number of blue-collar Republican voters and an average number of conservative, evangelical Christians — Wisconsin would seem a much better fit for Trump than for his chief rival, Ted Cruz. The Texas senator has relied heavily on religious conservatives for his victories so far.

Instead, Trump trailed Cruz by 10 percentage points, according to the poll, released Wednesday by Marquette Law School, which has a strong track record for accurately forecasting the state’s elections. And that was before Trump began attacking Wisconsin Gov. Scott Walker, who remains very popular with Republicans here, in response to Walker’s endorsement of Cruz.

If the poll forecast holds up, it could be enough for Cruz to sweep the state’s 42 delegates under the winner-take-most rules of Wisconsin’s GOP primary. That would be a setback for Trump, who is barely on track to win the 1,237 delegates he would need to avoid a contested convention when Republicans meet this summer in Cleveland.

The poll showed Trump doing particularly poorly with Republican women, among whom Cruz had a 15-point lead. Thursday, the Cruz campaign sought to reinforce that edge, sending Cruz’s wife, Heidi, and former candidate Carly Fiorina to campaign through three of Wisconsin’s smaller cities. Heidi Cruz was a central figure in last week’s Trump drama — an extended series of exchanges between Trump and Ted Cruz over which candidate had attacked whose wife first.

Julie Vajda, 45, a physician assistant in Appleton, is the sort of voter Trump’s rivals are targeting. She plans to vote for Cruz, she said, partly because she sees Trump as sexist.

“I find him to be disrespectful and derogatory toward women,” she said. His comments, including remarks he’s made about his daughter Ivanka, are “odd and inappropriate,” she added. “I don’t want that representing my country.”

Democrats, of course, were happy to pile on, seeking to keep alive the controversy Trump kicked off with his abortion comments and then his follow-up statement in which he abruptly shifted position, saying that doctors, but not women, would need to be punished for illegal abortions.

“Donald Trump is showing us exactly who he is, and we should believe him,” Hillary Clinton, the Democratic front-runner, said during a rally at a state university campus in a New York suburb. “For many young women today, it’s almost hard to imagine turning the clock back. But for those of us who have been around a little longer, we know what this means. So we’ve got to defend our rights.”

Clinton also criticized her Democratic rival, Sen. Bernie Sanders of Vermont, for saying during an interview on MSNBC that Trump’s remarks were a distraction from “a serious discussion about serious issues facing America.”

“To me, this is a serious issue. And it is a serious discussion,” she said.

Trump’s other Republican rival, Gov. John Kasich of Ohio, went after him on a different topic at a news conference in New York, criticizing Trump’s recent comments suggesting that Japan and South Korea should consider building their own nuclear weapons.

The comments indicated Trump was “really not prepared to be president,” Kasich said. That marked an escalation of language from Kasich, who has tended to avoid direct criticism of Trump.

Trump’s schedule suggests that he thinks his chances in Wisconsin are poor: He spent Thursday in Washington, holding meetings at GOP headquarters, and has not announced plans to return to Wisconsin until Saturday.

All that gives cheer to Trump’s adversaries in the GOP.

“It seems like the wheels are coming off a little bit,” said Henry Barbour, a prominent Republican strategist who has backed Trump’s rivals. “It’s not been a good few days, and Wisconsin seems poised to send a message that Donald Trump is not their kind of candidate.”

Trump’s campaign aides did not respond to requests for comment. The candidate himself has begun to complain that he is being treated “unfairly” by Republican rivals. On Tuesday night, he publicly renounced the pledge he had agreed to in the fall to back the GOP nominee if he loses.

The next round of primaries after Wisconsin could be kinder to Trump, particularly in his home state, New York. Still, he has yet to win more than 50% of the vote in any of the 31 states that have held GOP primaries or caucuses.

In a nationwide poll released Thursday by the nonpartisan Pew Research Center, 41% of Republicans and Republican-leaning independents surveyed said they wanted to see Trump get the party’s nomination; 52% supported someone else.

The share of voters overall who said Trump would be a terrible president hit 44%, Pew found, up from 38% in January. Among Republicans, at least half of those backing Cruz or Kasich said Trump would be either terrible or poor as president.

Only 38% of Republican voters in the poll predicted the party would unite solidly behind Trump if he were the nominee. That’s a sharp contrast to the Democratic race, in which 64% of the party’s voters polled said they expected Democrats would unite behind Clinton if she wins, a number on par with previous nominees in both parties.

Numbers like that should send a message to Republican convention delegates, say some of Trump’s critics in the party.

“Any candidate that looks like an almost sure loser in a general election is going to have a hard time getting a party’s nomination,” said Republican pollster Whit Ayres, who was a top strategist for Florida Sen. Marco Rubio’s unsuccessful bid. “The weaker Trump looks as a potential nominee, the greater the pressure to open up the nominating process for someone who might actually win the general election.”

Lauter reported from Washington and Finnegan from Green Bay. Times staff writers Chris Megerian in Appleton, Wis., and Evan Halper in Purchase, N.Y., contributed to this report.

For more on Campaign 2016, follow @DavidLauter and @FinneganLAT

ALSO

Trump is about to blow up the California primary

Abortion stumble displays Trump’s general election weakness

Voters don’t see Hillary Clinton as having moved to the left