Democratic U.S. Senator Amy Klobuchar is highlighting her work across the aisle as she runs for reelection, while her Republican opponent, state Rep. Jim Newberger, is accusing her of being a liberal rubber stamp.

Klobuchar and Newberger squared off Friday in an MPR News debate at the Minnesota State Fair. They clashed on many issues, including climate change, military spending and tax cuts.

Klobuchar, a former Hennepin County Attorney, made her case for reelection by saying she focuses on bread and butter issues for Minnesota. Klobuchar noted that she's been the lead Democrat on 18 bills signed by President Trump.

"You need someone that can find common ground but is also willing to be a check and balance on this administration," she said.

Newberger, a paramedic serving his third two-year term in the Minnesota House, said the state needs a conservative voice in the Senate.

"If you're in the moderate middle all the way to the conservative right you have not had a voice for almost decade," he said. "Folks, it's time that you had a voice. It's time you had a senator that does something for you."

Immigration was one of several points of contention during the debate.

Newberger, a three-term state legislator, said he would back Trump's border wall.

"We must build the wall," he said. "We must secure our border. The simple analogy is this: If you don't believe in building the wall or securing the border, then leave your front door wide open all day long 24 hours a day, seven days a week. If that doesn't bother you, then leave it wide open, and let anyone who wants come into your house and do what they care to do."

The Republican candidate also brought up the recent killing of an Iowa college student and alluded to the immigration status of her alleged killer.

"If we would have had comprehensive immigration reform where we knew who was coming across our border, would Mollie have been killed in Iowa?" Newberger asked.

"First of all," Klobuchar answered, "the family has asked that people not politicize this tragic death."

Klobuchar added the man charged with the student's death should be prosecuted to the full extent of the law. She also said that she endorsed a path to earned citizenship for people who have been law abiding and that she supported more money for border security and employer checks of immigrant status.

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With the Senate moving closer to confirmation hearings of President Trump's latest Supreme Court nominee, Klobuchar had plenty to say about Brett Kavanaugh. Klobuchar said Kavanaugh is not the nominee the country needs right now.

"When you look at the record of this nominee, you see someone who has not been in the mainstream," she said.

Newberger accused Klobuchar and other Democrats of trying to derail the Kavanaugh nomination.

"Right now they want to hold it all up. They want to wait until after the midterms so they can go in there and change this, and change our court with political ambitions," he said.

Klobuchar also differed with Newberger on the value of Special Counsel Robert Mueller's investigation.

Klobuchar didn't say whether she believes President Trump broke any laws, but she said it's vital for an independent investigation to continue.

"There are voices that want to shut it down. I think we have to get to the bottom of the truth," she said.

Newberger said the investigation has been politicized in an effort to build an impeachment case against Trump. But Newberger didn't call for an immediate end to the Mueller investigation.

In his first statewide campaign, Newberger aligns himself closely with the president's agenda. He praised last year's federal tax cuts and said the Russia investigation is distracting from important accomplishments.

Klobuchar later took aim at Newberger on climate change. She said his denial of the problem is out of step with the Senate.

"When I look at this, it is a real problem," Klobuchar said. "You could see a starker difference between me and my opponent, where he won't even admit that it is occurring, which is against science."

Newberger tried to clarify his position.

"Do I believe in climate change? Yeah, I do. I believe in climate change," he said. "Do I believe it's man-made? No, I do not. Climate change, the number one factor in climate change is the sun, and we cannot change the way the sun operates."

When asked about her intentions, Klobuchar pledged to serve a full six years if she wins a third term this fall.

"Of course I will," Klobuchar said. "I think my track record shows that. I love working in the Senate. I love representing Minnesota."

Klobuchar has been mentioned as a potential 2020 presidential contender or someone who could join a Democratic administration in the years ahead.

Newberger said he'd commit to six years, but suggested U.S. senators overstay their welcome after two terms.

"This is a strong argument for term limits, which I support. Eighteen years folks is a long time to be in the swamp," he said.

The Klobuchar-Newberger race is one of two U.S. Senate contests on Minnesota ballots this year.