Carl DeMaio, a former city councilmember from San Diego will announce Thursday that he plans to challenge vulnerable freshman Rep. Scott Peters, a Democrat.

Republicans recruited DeMaio, who is openly gay, to run in the 52nd District. In a release from his campaign, DeMaio refers to himself as a “new generation Republican” — just a few weeks after GOP polling showed him leading Peters by 10 points in a hypothetical matchup.

Peters, who also served as a San Diego councilmember, unseated longtime Republican Rep. Brian P. Bilbray in 2012 in one of the closest races of the cycle. The district has a slight Democratic lean, and voted for President Barack Obama in 2012 with 52 percent.

DeMaio served on the San Diego city council from 2008 until 2012. In 2012, he waged an unsuccessful campaign for mayor of San Diego, losing to former Democratic Rep. Bob Filner.

“If we want better results from Washington, we have to change the people we send there and impose new reforms to govern the way they operate,” DeMaio said in the release announcing his candidacy. “That’s what my reform agenda is all about — making government work again for the people.”

Earlier this year, the Democratic Congressional Campaign Committee placed Peters in its Frontline Program for vulnerable incumbents. The program helps bolster Democratic incumbents with fundraising and outreach support.