After Rep. Paul Gosar’s six siblings appeared in campaign ads for his opponent, the Arizona Republican placed the blame on former President Barack Obama.

Gosar is running for re-election in Arizona’s 4th congressional district, which he’s represented since 2013. Six of his siblings recently appeared in campaign ads supporting his opponent, Democrat David Brill.

Gosar told KFYI-AM that “it does sting” that his siblings turned against him in the ads. He said his children have taken the ads “very negatively” as well.

“You know, blood is supposed to be thicker than water,” Gosar told radio host Mike Broomhead.

Gosar added that his siblings’ move was indicative of what liberals have been instructed to do by political leaders.

“But, you know, this actually details exactly what the left, what Barack Obama, actually asked progressives to do, is to get into family and friends, in their face and not let up.”

FOX NEWS MIDTERM ELECTION HEADQUARTERS

One television ad featured interviews with Gosar’s siblings who asked voters to usher their brother out of office because he has broken with their family’s values. Several of his siblings had previously condemned the congressman’s false accusation in 2017 that wealthy Democratic donor George Soros was a Nazi collaborator in World War II.

“It's intervention time,” Tim Gosar says in the ad, endorsing Brill. “And intervention time means that you go to vote, and you go to vote Paul out.”

REP. PAUL GOSAR’S OWN SIBLINGS ENDORSE DEMOCRATIC OPPONENT IN SCATHING AD

In another video segment, the siblings urged voters to hold the congressman accountable on health care, employment and environmental issues.

Gosar addressed the advertisement in a series of tweets, calling his siblings disgruntled supporters of failed 2016 Democratic presidential nominee Hillary Clinton from out of state who put ideology before family.

“My siblings who choose to film ads against me are all liberal Democrats who hate President Trump,” Gosar said. “Stalin would be proud.”

The 4th congressional district encompasses the western and northwestern part of Arizona.

Fox News’ Kathleen Joyce and The Associated Press contributed to this report.