CNN revealed Tuesday night that the frontrunner in an Alabama Senate race has repeatedly questioned President Barack Obama's citizenship, and did so again late last year — even after Donald Trump backed away from the claim.

Judge Roy Moore, who won the first round of the Alabama GOP Senate primary this August, began expressing doubts about Obama’s citizenship in 2008 and has done so at least through December 2016, CNN’s Andrew Kaczynski and Paul LeBlanc reported. (Also a former champion of the conspiracy theory, then-presidential candidate Trump held a press conference in September of last year designed to distance himself from the birther claim.)

Moore will face incumbent Sen. Luther Strange in a runoff in the Alabama Senate primary on September 26, after none of the 10 candidates in the first round cleared the necessary 50 percent of the vote to avoid a second round. Moore beat Strange in the race’s first round by about 10 points.

Moore holds a host of policy positions that put him far afield from what at least used to be the Republican Party mainstream. Famous for refusing to take down a monument to the Ten Commandments from his courthouse, and then again for refusing to issue marriage licenses to same-sex couples, Moore has defied federal court orders, addressed a white supremacist group, penned invectives against Perez Hilton over same-sex marriage, and argued that Rep. Keith Ellison (D-MN) should not be seated as a Congress member because he is Muslim.

“Moore’s ideology is an express belief that God’s law and his interpretation of God’s law stand on top of man’s law,” David Dinielli, deputy director of the Southern Poverty Law Center, told me. “It’s an ideology that would allow those who think they know the unknowable and the mystic to impose their beliefs on everyone else.”

Most recently, Moore told the Constitution Party in December 2016 that it wasn’t his “personal belief” that Obama was born in the US.

"My personal belief is that he wasn't, but that's probably over and done in a few days, unless we get something else to come along,” Moore said, according to video reviewed by CNN.

He also said in 2008 in an interview with WorldNetDaily: "I don't see any reason a candidate who has such a serious question would not come forward with the truth about where he was born.”

Moore’s spokesperson, Katie Foster, did not return multiple requests for comment.

A poll published Monday found Moore leads Strange by 19 points.