Republican congressional candidate Carl DeMaio has acknowledged that a report he presented to the press as his own, and that the National Journal said appeared to be plagiarized, should have credited the Journal as the source. DeMaio told the Journal that he was “mortified” about the error. However, DeMaio’s stands by the thrust of his accusation that incumbent Democrat Rep. Scott Peters had “double dipped” into government pensions.

DeMaio’s report highlighted 102 members of Congress who are collecting pensions from other government jobs at the same time that they earn a congressional salary–except Sen. John McCain, who is collecting a military pension. One of those 102 members was Peters, according to DeMaio. The Peters campaign claims he tried to refuse the pension, and donates it–plus $5,000–to local libraries, while refusing a federal pension and benefits.

On Monday, DeMaio told Breitbart News that Peters’s claims were not true, and that he could have refused a San Diego pension, just as DeMaio himself did in his time on the city council. He went on to assert that Peters only donated his pension after DeMaio criticized him in 2010 for taking it. DeMaio again acknowledged that his staff had used the National Journal report, but added they had also done their own research to substantiate it.

The race for California’s 52nd congressional district is one of the most hotly contested in the country, with analysts calling it a “pure toss-up.” DeMaio is seen by some as the “establishment” Republican choice, and has also gained national attention as one of few openly gay Republicans running for public office. DeMaio lost to Democrat Bob Filner for mayor of San Diego in 2012. Filner later resigned over a sexual harassment scandal.

The other two Republicans challenging for the seat are Marine Corps combat veteran Kirk Jorgensen and physician Fred Simon. The open primary election, in which the top two vote recipients will advance, is June 3.

Photo: Gregory Bull/AP

Joel B. Pollak contributed to this report. Full disclosure: Moons is a treasurer for the Jorgensen campaign.