MONTGOMERY, Ala. — Alabama Sen. Luther Strange and challenger Roy Moore on Thursday night traded jabs in a contentious debate, as they sought to sway voters ahead of the state’s closely watched U.S. Senate primary runoff.

Politeness was quickly abandoned in the moderator-free debate, as the two Republicans swapped barbs for more than an hour over Strange’s appointment to the Senate seat, Moore’s knowledge on federal issues and the millions of dollars being spent in the high-stakes race.

The winner of next Tuesday’s GOP runoff will face Democrat Doug Jones in a December election to serve out the rest of Attorney General Jeff Sessions’ term, ending in January 2021.

Strange, the state’s former attorney general who was appointed to Sessions’ former seat in February, is trying to fend off a challenge from Moore, a darling of evangelical voters after being twice removed as state chief justice upon taking losing stances against gay marriage and in favor of the public display of the Ten Commandments.

Strange is backed by President Donald Trump and millions of dollars in donations from allies of Senate Majority Leader Mitch McConnell. Moore is supported by a number of anti-establishment forces, including former Trump chief strategist Steve Bannon as well as the Great America Alliance, an advocacy group that supports Trump. Former vice presidential candidate Sarah Palin headlined a Thursday night rally for Moore.

Strange reiterated his Senate support from Trump, who is expected to speak at a Friday night rally in Huntsville. Vice President Mike Pence is coming to the state Monday to back Strange.

“Who does the President support? The president supports me,” Strange said. Trump fired off a tweet in support of Strange as the debate began, saying that Strange would be great in Washington.

During the debate, Strange tried to distinguish himself as the more knowledgeable and accomplished candidate, referring to his work as senator and saying he spent “six years fighting the Obama administration” as state attorney general by suing over clean power rules and other matters.

“The future of this country is at stake. Who is going to help the president?” Strange said.

Moore fired back that the “elitist Washington establishment” was spending millions of dollars to try to secure the race for Strange while refusing to enact Trump’s agenda.

“I want to tell you the people of Alabama see through this. They see what Washington is trying to do and they’re upset,” Moore said.

Moore took aim at Strange’s background as a federal lobbyist, a fact that he said was at odds with Strange’s claim that he wants to “clean up the swamp.”

“You don’t get rid of lobbyists in the swamp by sending them to the United States Senate,” said Moore.

Moore criticized Strange for accepting the office from a scandal-plagued governor at a time when his office was in charge of corruption investigations. The former chief justice said Strange had been vague when asked whether his office had opened a direct investigation into then-Gov. Robert Bentley when Bentley appointed Strange to the U.S. Senate.

“What’s the truth?” Moore asked from the stage.

Strange did not answer Moore’s question in his rebuttal time, but has said there was nothing inappropriate with the appointment. Bentley later resigned after pleading guilty to a misdemeanor campaign finance violation.

Tickets to the debate were split evenly between the two campaigns. Moore’s supporters ignored the request to limit applause, breaking out in loud cheers. Strange’s devotees soon followed suit.

As Strange repeatedly mentioned Trump, Moore quipped that he wasn’t running against Trump, but rather Strange.

Strange said Moore’s supporters look like the White House “unemployment line,” an apparent reference to Moore’s support from past Trump advisers such as Bannon.