NRCC hits ex-Rep. Joe Baca with Web ad

The group's decision to attack Baca is noteworthy, as he's not the only Democrat in the race.  Redlands Mayor Pete Aguilar (D) is also running after being recruited by the Democratic Congressional Campaign Committee. Baca, who lost a reelection bid in a neighboring district last cycle, has a more conservative voting record, and the attacks indicate the GOP may feel he'd be the tougher candidate to beat in the general election.

The ad seeks to tie Baca to House Minority Leader Nancy Pelosi (D-Calif.) and paint him as too liberal, though the DCCC has been touting Aguilar's candidacy. The Redlands mayor ran against Miller last year but didn't make the second round of the all-party primary, and Miller defeated another Republican to win an election in a district that went comfortably for President Obama.

Miller is the most vulnerable GOP incumbent up for reelection this cycle.

"It's party time. A Pelosi-palooza. Former Congressman Joe Baca wants his old job back, and Nancy Pelosi is throwing him a party. But don't get excited just yet," the ad's narrator says. "In Congress, Joe was one of Pelosi’s biggest supporters. That's right. Joe supported the failed stimulus, cuts to Medicare, even a national energy tax. No wonder Nancy Pelosi wants Joe back: He'll put her first and California families last. Tell Joe and Nancy: The party's over."