Republican Sen. Susan Collins and Democrat Troy Jackson met Tuesday night in Portland for the first of four debates in Maine's Senate race. The hour-long debate aired on WGME-TV. It was often testy but stayed civil.

Jackson tried to tie Collins to President Donald Trump. He named Trump at least 20 times, NBC News counted, and said she votes with him 96% of the time. Collins said the study he cited looked at only about a third of her votes. She said it also found she broke with her party more than any other senator.

Asked if she would stand with Trump if he came to Maine, Collins said she did not expect him to come. "I've heard nothing from his office, and I'm not exactly his favorite senator," she said.

The debate fell on the eighth anniversary of Collins' vote to confirm Justice Brett Kavanaugh. Jackson asked voters whether they would trust her "to pick the next Supreme Court justice." Collins said she judges nominees on their qualifications and disagreed with the ruling that ended Roe v. Wade. She then noted that Jackson opposed abortion earlier in his career. "There's only one of us on this stage who has always been pro-choice, and that's me," she said.

They also fought over Trump's big tax and spending law. Collins voted against it at the end but voted to let it move forward earlier. Jackson called her "an arsonist who helped set the fire." Collins said that step helped her win a $50 billion fund for rural hospitals.

Both criticized Trump's tariffs on Canada. Collins said she got road salt taken off the tariff list. "We can't eat road salt," Jackson replied. On immigration, Jackson said ICE should be disbanded, while Collins said it needs reform, not an end.

Collins is seeking a sixth term. She is the only Republican senator from a state Trump lost in 2024. Jackson became the Democratic nominee late, after primary winner Graham Platner dropped out. Polls show a very close race. The full debate video is posted on C-SPAN.

What we know: Three more debates are planned.
What we don't: Whether Tuesday's clash moves a race that polls show is close.