PORTLAND — During the final debate of this election season, the three candidates competing for Maine’s open 2nd Congressional District seat were taken to task on the claims they have made and attacks they have leveled at each other.

Democratic nominee Emily Cain was asked by the moderator, WCSH-TV anchor Pat Callaghan, about the claim that she, as the House minority leader in 2011, negotiated the largest tax cut in Maine’s history.

Cain has made the claim in an effort to dispel the notion that she’s a tax-and-spend liberal, but at the time the budget passed, she said she hated the cuts.

“How can you have it both ways?” Callaghan asked.

“Then I was definitely speaking for my caucus,” Cain said. “There was a lot of discontent around that initial tax package. We made changes to that tax package to make it better. We lowered the income tax. We worked to make sure the estate tax worked better for Maine families.”

Bruce Poliquin, former state treasurer and Republican nominee, was asked whether it was ethical for him to enroll his Georgetown oceanfront property in Maine’s Tree Growth Tax Program, even though there were restrictions on the property that largely prevented tree harvesting. The program gives tax cuts to landowners whose property can be used for commercial harvesting.

Rather than answer the question, Poliquin attacked Cain.

“This is a good example of Emily Cain simply not telling the truth,” he said. The allegation has been mentioned in Cain’s TV advertisements.

“I have always paid all of my taxes, in full, all of the time,” Poliquin said.

When pressed to answer whether it was ethical, Poliquin repeated the statement.

Blaine Richardson, the independent candidate in the race who once worked as a code enforcement officer in Rockport, said the question is not whether you pay your taxes, it’s how you behave as a property owner.

“There is a certain amount of ethics that go along with the stewardship and ownership of property,” he said. “Quite frankly, in Rockport, you used to see the same thing — private individuals clearly taking advantage of Tree Growth.”

Cain and Poliquin are locked in a tight race to replace U.S. Rep. Mike Michaud, the Democratic nominee for governor.

The most recent public polls have shown conflicting outcomes, though Richardson is trailing with poll numbers in the single digits.

At Thursday night’s debate, some of the refrains voters have heard from the candidates over the past few weeks were repeated.

Poliquin continued to paint Cain as a career politician from out-of-state and reiterated that as a businessman, he is the best candidate to improve Maine’s economy.

“Emily came to Maine to go to our university,” he said. Cain went to the University of Maine and has lived in the state since then.

“We the taxpayers helped foot part of the bill to pay for her education and then when she went into the Legislature, the taxpayers paid her salary,” Poliquin said.

Cain said that she stood by her record in the Legislature, where she served since 2004, and said that her experience working with Republicans on budgets would help her in Washington.

Richardson, a retired Navy captain from Belfast, often was left out of the fray during the 30-minute debate. When given the chance, he presented himself as the candidate who could rise above the party politics.

“In the end, what we see here is partisan bickering and it’s not leadership,” he said.

The candidates were asked what they would change about the Affordable Care Act.

All three said the law had problems, but only Richardson said he would repeal it. Both Poliquin and Cain said it was harming small businesses, though neither offered specific ways they would improve it.

The debate was televised by WCSH-TV and was hosted at the TV station’s studio in Portland. It is the last of four debates that the three candidates will participate in during this election cycle.

Earlier on Thursday, Cain’s campaign told WMTW-TV that she would not be participating in that TV station’s debate, scheduled for next Tuesday, because Richardson had not been invited. As a result, that debate has been canceled.