Prop 50 passes in California, boosting Democrats in fight for US House control

California voters resoundingly approved Proposition 50, the ballot measure championed by Democrats to enact new congressional maps ahead of the 2026 midterms — a fight that became as much a referendum on President Donald Trump as a question of redistricting.

In passing Proposition 50, voters agreed to temporarily set aside the maps drawn just a few years ago by the state’s popular independent redistricting commission and approve congressional boundaries aimed at giving Democrats five more seats in the House of Representatives. The measure, championed by Gov. Gavin Newsom, was a direct response to Trump’s demands that GOP-led states, including Texas, rework their congressional boundaries to benefit the president’s party ahead of the midterm elections.

Newsom and Democrats framed the fight as a way to safeguard democracy and check the president’s power, while Republican opponents focused their message on the popularity of the independent commission, the cost of an off-year special election and what they described as the unfairness of the new maps.

But in a state where Democrats hold a 20-point registration advantage over Republicans, defeating the measure proved to be an uphill battle for the GOP.

Mark Baldassare, director of the Public Policy Institute of California’s statewide poll, said that’s in part because voters viewed Proposition 50 through an unusually partisan lens for a ballot measure.

“The polarization is very much in line with what we have seen in candidate races,” he said.

Baldassare said that for 20 years, the PPIC poll has asked voters the same question when there’s a ballot measure: How important is the outcome to you?

“In the case of Proposition 50, 68% of likely voters said that the outcome of this election is very important to them,” he said. “I’ve never seen a number this high. And I think it’s this high because Proposition 50 is not just about what’s going on in the state. It’s about what is going on in the nation.”

The passage of the measure now kicks off a scramble in the five newly drawn districts. Congressional hopefuls must declare their candidacy by early March to appear on the June primary ballot.

Erin Covey, who leads The Cook Political Report's coverage of the U.S. House, said California could be hugely consequential next year as Democrats and Republicans fight for control of Congress.

That’s because, in addition to the five districts drawn to give Democrats an edge, the new maps made eight other congressional districts already held by Democrats even safer.

“So this could certainly determine who controls the house in 2027,” she said.