Sen. Thad Cochran (R-Miss.) (AP Photo)

A super PAC supporting Sen. Thad Cochran (R-Miss.) will release its final commercial of the primary campaign Thursday, a 60-second radio spot that says state Sen. Chris McDaniel (R) "doesn't tell the truth."

"McDaniel calls himself a lifelong Republican, but when Haley Barbour ran for governor, McDaniel voted in the Democrat primary," says the narrator of the ad from Mississippi Conservatives, which was shared first with Post Politics. "When asked about it? He lied."

McDaniel previously disputed records saying he voted in the Democratic race in 2003.

The ad also says McDaniel once argued against tort reform in court, even as he says he supports it. And it seeks to draw attention to McDaniel missing "118 votes" in the state Senate.

"So who is Chris McDaniel really? He’s a personal injury lawyer who will say and do anything to win. A state senator who doesn't show up for work. A politician who doesn’t tell the truth," the ad concludes.

The group said it is spending $80,000 to air the commercial.

The commercial comes with just days left before the June 3 primary. The arrest of a McDaniel supporter for allegedly photographing Cochran's bedridden wife and posting at least one photo of her in an online video has upstaged everything else in the campaign during the stretch run.