It is one of the closest races in the country that could shake up the balance of power in the US Senate, and the first debate Monday was right in our backyard.

The first of two televised debates in Pennsylvania’s U.S. Senate race between Republican incumbent Sen. Pat Toomey and Democratic challenger Katie McGinty was hosted by KDKA-TV Monday in its Gateway Center studio.

Sen. Toomey was first elected to the Senate in 2010 after previously serving in the House of Representatives from 1999-2004. McGinty was defeated by now-Governor Tom Wolf in the 2014 Democratic Primary and later served as his chief of staff. She is also the former secretary of the Pennsylvania Department of Environmental Protection.

The GOP currently holds a 54-46 majority in the Senate, but Toomey is among the Senate’s most vulnerable in 2016 to lose re-election. The most recent RealClearPolitics polling average has McGinty ahead by just 0.4 percentage points.

Toomey has been criticized nationally for not announcing his position on Republican presidential candidate Donald Trump. He is the only Senate candidate to not take a stand on Trump. He has denounced his comments, but said he has not made a decision about the top of his party’s ticket.

Moderator Ken Rice, a KDKA-TV anchor, wasted no time asking the candidates about their positions on their party’s presidential nominee.

McGinty said she fully supports Hillary Clinton for president. Toomey deflected the question back on McGinty, saying she is extremely partisan on issues.

Rice asked Toomey multiple times about his position on the presidential candidate, but Toomey would not take a position.

“Because Katie is so extremely partisan, she can’t grasp that somebody might have trouble with a candidate in their own party. But I do,” Toomey said. “I’ve been very public about my many disagreements with Donald Trump. I have been willing to criticize him because I think he’s a badly flawed candidate.”

“On the other hand, I also know that if he were president, he’d probably sign legislation that would be constructive. I can’t believe Katie McGinty can’t criticize anything about Hilary Clinton, including all of her lies. Maybe that’s because Katie started her campaign with a big fat lie herself.”

Toomey was referring to McGinty’s claims on the campaign trail that she is the first in her family to go to a four-year college directly out of high school. However her brother, John McGinty, graduated from La Salle, a four-year college, after attending Philadelphia Community College eight years before she entered Saint Joseph’s University.

Therefore, McGinty was the first in her family to attend a four-year college, but not the first to attend college period.

“If Katie McGinty started her campaign with a fundamental lie about her very own life story, how are voters supposed to trust her about anything?” said Toomey for Senate Spokesman Ted Kwong in a press release.

Toomey brought up McGinty’s education claims multiple times throughout the debate and had another chance to call her a liar later in the debate.

When discussing the topic of police-community relations, Toomey promoted the multiple endorsements he has received from law enforcement organizations across Pennsylvania, including the Pittsburgh Police, saying none of them have endorsed McGinty.

“That’s not true,” McGinty said. “I have been endorsed by law enforcement organizations as well.”

The two exchanged words, but she could not list a specific police organization that has endorsed her.

McGinty’s campaign later clarified on Twitter that the International Union of Police Associations endorsed her, but the IUPA actually endorsed Toomey in March.

Her campaign then said it was the Pennsylvania chapter of the IUPA that endorsed her, but no state chapter actually exists.

The IUPA does, however, have a local chapter in Pittsburgh that represents 34 Port Authority Transit Police. That was that organization that actually endorsed McGinty, the daughter of a Philadelphia police officer.

The race is currently the most expensive in the country. More than $90 million has been spent on the Pennsylvania Senate election that has a chance of surpassing the $112 million 2014 North Carolina Senate election that was the most expensive in history.

The debate covered a wide range of other topics, including gun control, U.S. Supreme Court nominees and environmental issues.

The final question asked by Rice dealt with Trump’s claims that the election may be rigged. Toomey said it was “maybe the most important question of the evening.”

“Our elections may not always be completely perfect, but they are legitimate,” Toomey said. “They have integrity. Everyone needs to respect the outcome. That’s going to be necessary to pull us all together the day after the election.”

Both candidates addressed the media afterwards, where Toomey deferred to his debate comments when asked again about supporting Trump.

When asked if he thought he won the debate, Toomey answered without hesitation.

“Yeah, I think I won the debate,” he said. “It was a good debate. It was quite a vigorous back and forth, but I’m very pleased with how I did.”

McGinty was asked the same question.

“I think this is about the people of Pennsylvania winning,” McGinty said. “I think that if you’re ready to be paid a decent wage, have decent schools, and get back to work doing things like rebuilding our infrastructure, it’s a win that we have a chance here to make a change. I’d be honored to go to bat for hard-working Pennsylvanians every day in Washington.”