TOLEDO, Ohio — Heather Tabbert, who works as a waitress at a Waffle House here, has been a Democrat all her life, but this year the only thing she is certain about in the presidential race is that she won’t vote for Democratic nominee Hillary Clinton.

Maybe she’ll stay home on Nov. 8. Maybe she’ll vote for Republican nominee Donald Trump.

“I don’t know about either of them, but If I was going to vote, it would probably be for Trump, because if Hillary gets it, nothing will change,” she said on a recent morning as she served up waffles, eggs and hash browns.

Mrs. Clinton, who has made her bid to make history as the first female president a centerpiece of her campaign, has hit an unexpected rough patch with women voters in this key battleground.

Weak support from women would deliver another blow to Mrs. Clinton’s attempt to reassemble President Obama’s hope-and-change coalition that twice won him the White House.

Throughout the campaign, the former secretary of state has struggled to attract young voters who were another powerful component of the Obama coalition.

Attempting to coax more female voters into her campaign, Mrs. Clinton deployed her daughter Chelsea Clinton for two events Thursday in this solidly Democratic city, where economic struggles have helped Mr. Trump forge inroads.

At a campaign organizing event at the University of Toledo, the younger Ms. Clinton stressed how this election took on extra meaning for her because it was the first time she would cast a vote for president as a parent.

“This election is so personal for me because I know whoever we elect will play a profound roll in shaping the world my children and the children here today grow up in,” she told the crowd of about 200 people.

Mrs. Clinton’s supporters enjoyed seeing her daughter, but many said the candidate needed to show up in person to shore up support in Toledo, where Mrs. Clinton can’t afford to lose Democratic votes.

Female voters such as Ms. Tabbert, who doesn’t closely follow politics, say they are put off by the Clinton scandals — the secret email, Benghazi, the Clinton Foundation — but mostly they are resistant to the status quo in Washington that they think Mrs. Clinton represents.

Joyce Herwat, a 62-year-old homemaker, said she wasn’t just through with Mrs. Clinton but had given up on the Democratic Party and become a die-hard Trump supporter.

“I got so fed up with them. From the time I could first vote, I was a Democrat. I don’t recognize the party anymore.” Ms. Herwat said.

She is one of more than 115,000 Democrats who switched to Republican this year in the Ohio primary in March, compared to nearly 35,000 who switched the other way, according to the Ohio secretary of state.

Mrs. Clinton continues to outperform Mr. Trump among women, especially college-educated women. But her advantage with the demographic has slipped in Ohio.

Mrs. Clinton led Mr. Trump among Ohio women likely to vote by just 2 points, 44 percent to 42 percent, according to a Fox News poll of likely Ohio voters released Wednesday.

By comparison, Mr. Trump’s advantage over Mrs. Clinton with male voters was 13 points, 49 percent to 36 percent, as he continued to dominate that demographic.

Overall, Mr. Trump topped Mrs. Clinton by 5 points, 45 percent to 40 percent. It was the latest in a series of surveys showing Mr. Trump taking the lead in this crucial battleground.

The weak support from women and young voters, coupled with Mr. Trump’s surge in the polls, struck fear in some Clinton supporters in Toledo.

When Ms. Clinton dropped by her mother’s campaign office in the city, several supporters and volunteers said they appreciated the visit, but the candidate herself should be showing Toledo some love.

“We’re worried; Ohio is so important. We have to win Ohio,” said Ann Petlow, 34, a Clinton volunteer.

“In Toledo we’re used to getting the candidate. It’s a little iffy getting a surrogate,” she said. “We are used to getting wooed. She should come here herself.”

Annette Shine, 62, a retired chemical engineer, agreed.

“She needs to come here so people don’t get complacent or think she doesn’t care,” said Ms. Shine. “She should come at least once. People like to feel that they matter.”

Toledo attorney Jeff Goldstein, 72, who attended the Chelsea Clinton drop-by event, said he was mystified that Mrs. Clinton wasn’t getting more support form women.

“How any woman could vote for [Mr. Trump] I don’t know, with all the anti-woman things he has said,” he said.