California Democratic Rep. Doris Matsui has advanced to the November ballot after facing a reelection challenge from a younger Democrat.

Matsui, 81, has been in Congress since she replaced her late husband, former Rep. Bob Matsui, in the Sacramento-based seat in 2005.

She faced a primary challenge from fellow Democrat Mai Vang, a member of the Sacramento City Council, and is one of several older Democrats challenged by younger insurgents this year.

California’s primaries are helping set the stage for the fall battle for the House of Representatives and testing whether Democrats are able to add five potential pickups after they persuaded voters to let them redraw the electoral map last year.

The redistricting was sold as a countermeasure to Republican efforts to gain seats by reworking maps in states they control, including Texas.

Heading into Tuesday’s election, Democrats worried that California’s primary format, which sends the top two vote-getters to the general election regardless of party, could lead to them getting locked out of a seat they drew to their advantage in the San Diego’s suburbs.

That did not happen, as San Diego City Councilwoman Marni von Wilpert advanced to face Republican Jim Desmond, a San Diego County supervisor. But Democrats are at risk of being shut out of another district they expected to pick up, in Sacramento’s suburbs.

A wealthy progressive challenger was unable to crack the top two slots in San Francisco to fill retiring Rep. Nancy Pelosi’s seat. Instead state Senator Scott Wiener and city Supervisor Connie Chin will face off to replace the former House speaker.

And in the Central Valley, Republican Rep. David Valadao, widely considered one of the most vulnerable House Republicans, is waiting to see if he will face centrist Democrat and Assemblywoman Jasmeet Bains or progressive political science professor and school board member Randy Villegas in November.

Nicholas Riccardi, The Associated Press