The top tier candidates in West Virginia’s Republican Senate primary sparred in Tuesday’s Fox News Channel debate over who is most conservative and more closely aligned to President Trump, while blasting Special Counsel Robert Mueller’s Russia probe.

U.S. Rep. Evan Jenkins denied being a creature of the swamp, despite enjoying the backing from Washington Republicans. He emphasized his support for Trump.

“You know, I proudly endorsed President Trump in the May primary, 2016,” Jenkins said. “The only one up here on the stage who did that and have been standing with him each and every day.”

Jenkins attacked West Virginia Attorney General Patrick Morrisey for past comments saying Trump wasn’t his first choice in the 2016 primary. But Morrisey boasted of his eventual backing of Trump at the convention and his opposition to former President Barack Obama's policies.

“We have a great relationship,” the attorney general said of Trump. “We work together. I was proud to run ads with the president and supported him at the convention.”

Meanwhile, former coal executive Don Blankenship portrayed himself as the true outsider in the race, saying he wouldn’t go to Washington to get along with people in the GOP leadership, like Senate Majority Leader Mitch McConnell.

“I'm not going to D.C. to get along, so that will be a failure because I don't intend to get along,” Blakenship said. “I intend to make sure that we make a difference.”

Ahead of the debate, Blankenship made waves for airing a campaign ad referring to McConnell, R-Ky., as “cocaine Mitch.” The origins of “cocaine Mitch,” according to the campaign, are rooted in accusations of drug smuggling on Chinese ships associated with the family of McConnell’s wife, Transportation Secretary Elaine Chao.

WEST VIRGINIA REPUBLICAN SENATE RACE: A LOOK AT THE TOP THREE CANDIDATES

The West Virginia Senate race is considered a toss-up in the midterm elections.

Republicans hope to unseat incumbent Joe Manchin, a Democrat who first won the seat in a 2010 special election.

The GOP establishment has expressed fear Blankenship's criminal history may jeopardize an opportunity to unseat Manchin.

Blakenship, who served a year in prison after being convicted on a conspiracy to violate mine safety standards, defended his actions tied to the 2010 Upper Big Branch mine disaster that killed 29 people and portayed himself as the victim of a “fake prosecution.”

“They sent me to prison for a misdemeanor, I was the only prisoner that was a misdemeanor,” Blankenship said. “It was clear from the beginning to the end that it was a fake prosecution.”

The hour-long debate, which took place at the Metropolitan Theatre in Morgantown, was moderated by Fox News’ Bret Baier and Martha MacCallum.

Asked if he accepts responsibility for the deaths of the miners, Blankenship said, “I am accepting the responsibility to do everything I can to keep it from happening again.”

Morrisey – who is originally from New Jersey and previously ran for office there -- defended himself against charges of carpetbagging.

“I feel very fortunate that I am one of the folks up here who moved to the states by choice,” he said. “I love West Virginia with all of the fiber in my being.”

CLICK FOR FULL MIDTERM COVERAGE AND RACE RATINGS

Like the others, Morrisey portrayed himself as the true conservative in the race.

“I think it is very clear of all of the candidates on the stage, I am actually the only one with a conservative record of results,” the attorney general said, noting his past efforts to sue the Obama administration over coal.

Jenkins and Morrisey dueled throughout the debate, with Jenkins at one point accusing Morrisey of being a hindrance to solving the opioid problem in the state.

“If you want to see what the problem is, it is the pill-pushers and Patrick Morrisey is representing those people for years and made millions,” Jenkins said.

But Morrisey shot back: “There he goes yet again. Did your mom ever tell you that we should wash your mouth out with soap with those lies?”

One thing all three candidates agreed on: blasting the special counsel investigation into the Trump administration’s ties with Russia.

“With respect to the Mueller investigation, I think it needs to come to an end,” Morrisey said. “It's a witch hunt. We need to stop that.”

“End this investigation now,” Jenkins said.

Blankenship, who spent a year in prison, quipped that he has “had a little personal experience” with the Justice Department. He said, “they lie a lot too.”

Jenkins, who leads the field of Republicans according to polling, has been a congressman for three years and served as a state senator in West Virginia for 12 years.

Morrisey is the first Republican to serve as attorney general in the state since 1933.

Blankenship was chairman and CEO of the Massey Energy Company.

Manchin is not running unopposed; he races a primary challenger in Paula Jean Swearengin, an environmental activist whose platform is more in line with Sen. Bernie Sanders, the progressive independent from Vermont.

Trump beat Democrat Hillary Clinton by more than 40 points in the Mountain State in the 2016 presidential election.

The state has long been considered a prime pickup opportunity for Republicans, who hold a two-seat Senate majority that suddenly feels less secure given signs of Democratic momentum in Nevada, Arizona, Tennessee and elsewhere. If Democrats can win West Virginia, which gave Trump his largest margin of victory in the nation, they may have a slim chance at seizing the Senate majority.

Fox News’s Peter Doocy, Kaitlyn Schallhorn and The Associated Press contributed to this report.