PITTSBURGH - Sen. Pat Toomey (R., Pa.) and Democratic challenger Katie McGinty accused each other of enriching themselves at the expense of ordinary people in their first Senate debate Monday, launching attacks that mirror the ads flooding the state.

At one point, Toomey conceded, "It's getting hard to watch TV."

His jaw often tensing, he repeatedly accused McGinty of starting her campaign with "a big, fat lie" about being the first in her family to go to college (a brother went first). He also said she supports regulations that would kill jobs.

McGinty painted Toomey as a rank partisan who "started his career on Wall Street and, in some ways, never left."

She noted that he owned a significant stake in a local bank while sitting on the Senate banking committee, and has opposed tougher banking regulations.

Neither candidate landed the kind of blow that seems likely to turn the tide in a tight race that appears increasingly important to control of the Senate.

But Toomey shed some light on his views on GOP presidential nominee Donald Trump, and sparring over police endorsements provided fodder that the incumbent seized for further attacks on McGinty's honesty.

The first of two hour-long debates taped at KDKA-TV in Pittsburgh aired Monday night.

Asked about Trump's assertions that the election may be "rigged" - and his frequent insinuations about shady results in Pennsylvania - Toomey said voters should respect the results of the Nov. 8 contest no matter who wins.

"Our elections may not always be completely perfect, but they are legitimate, they have integrity, and everyone needs to respect the outcome," he said. "That's going to be necessary to pull us all together on Nov. 9."

But while Toomey broke with Trump on this issue, his long-standing refusal to take a firm stand on the nominee dominated the early portion of the debate. McGinty and the KDKA moderators brought up the subject immediately.

Toomey said Trump would "probably sign legislation that would be constructive," such as repealing President Obama's health law and imposing new sanctions on Iran.

But, as he has before, he did not say whether he would support the Republican nominee. Toomey said he would "probably" announce his decision by Election Day.

McGinty hammered him for refusing to take a clear stand.

"Waiting to be persuaded is political speak for 'waiting for the next poll,' " McGinty said.

She said Pennsylvanians deserve an answer to the "straightforward" question and at one point yielded her time to Toomey so he could elaborate on his views.

"Katie is so extremely partisan, she can't grasp the idea that somebody might have trouble with the candidate in their own party," Toomey fired back.

McGinty faced one awkward moment when Toomey boasted about the numerous law enforcement groups that endorsed him.

"I have been endorsed by law enforcement organizations as well," she said, though when Toomey pressed her to name them, she did not answer.

Later, her campaign tweeted that she had been backed by the International Union of Police Associations, but that group's national organization has endorsed Toomey. She was actually endorsed by a local chapter of the union representing about 34 Port Authority Transit police in Pittsburgh.

Toomey's camp quickly pounced, calling the flap more evidence of McGinty's dishonesty. Her campaign downplayed it as a simple misunderstanding in the heat of a debate.

The debate brought out predictable partisan differences on issues such as climate change, the Affordable Care Act, campaign finance laws, and the Supreme Court.

The candidates, often overshadowed by the volatile presidential contest, also took the chance to try to round out their images.

McGinty often cited her personal story, saying she comes from "a hardworking family" and argued that she would look out for similar families now.

"There's only one of us on this stage who kissed her dad goodbye in the morning not knowing, after he walked his beat for 35 years . . . whether Dad was coming home for dinner," she said during the exchange on police.

The ninth of 10 children, she also talked about brothers who worked as coal miners when answering questions about climate policy.

Toomey painted himself as a fiscal conservative who opposes higher taxes, and "an independent voice" willing to cooperate with Democrats.

"Katie McGinty is not going to be that kind of person with any independence," he said.

He also sought to downplay his Wall Street years, saying he "worked in New York in finance in the '80s" and then launched a small business - a restaurant chain - with his brothers.

The second and final Senate debate is scheduled for Monday in Philadelphia.