LOS ANGELES (AP) — Barack Obama is entering the fight for U.S. House control by appearing in a 30-second ad urging California voters to approve a November ballot proposal that could add as many as five Democrat-held House seats in California.

Proposition 50 would dramatically reshape California’s congressional districts with the intent of adding Democratic seats in Congress. It’s crafted to gain Democratic House control, aimed at offsetting President Donald Trump’s moves in Texas and elsewhere to help win more Republican seats in the 2026 midterm election.

“Republicans want to steal enough seats in Congress to rig the next election and wield unchecked power for two more years,” Obama says in the ad, looking directly into the camera. “You can stop Republicans in their tracks.”

Democratic Gov. Gavin Newsom has framed the election as a referendum on all things Trump, who is unpopular in liberal-leaning California outside of his conservative base. Voting on the proposal is underway and concludes Nov. 4.

Republicans and other opponents say the proposal amounts to a Democratic power grab that would set aside district lines crafted by an independent commission that was created by voters more than a decade ago.

The duel between California and Texas, the nation’s two most populous states, has spread nationally. North Carolina Republican legislative leaders announced plans Monday to vote next week on redrawing the state’s House district map, taking up Trump’s call to secure more GOP seats nationwide and resist rival moves by Democrats.

Republicans hold a 219-213 majority in the U.S. House, with three vacancies.

If approved in California, it’s possible the new political map could slash five Republican-held House seats while bolstering Democratic incumbents in other battleground districts. That could boost the Democratic margin to 48 of California’s 52 congressional seats, up from the 43 seats the party now holds.