Rep. Ken Calvert, a congressional mainstay for more than 30 years, announced Wednesday will attempt to remain in Congress with a run in the newly drawn 40th Congressional District. Hours later, Rep. Young Kim said she'll run for re-election in the same district, setting up a showdown between the two Republicans in the 2026 midterm elections.

Following the passage of redistricting measure Proposition 50 in California, Republican Rep. Kevin Kiley said he'll definitely run for Congress but is still deciding for which district.

The 85-year-old Democratic leader didn't say why she isn't running for reelection. It comes as one lawmaker recently announced his bid for her seat.

The Democratic Congressman says he's seeking re-election for the redrawn district following the projected passage of Proposition 50.

California GOP looks for answers after Prop. 50 loss, Dodgers pitcher Alex Vesia and his wife mourn death of their baby daughter, and more big stories.

See below for a closer look at the districts that are being targeted.

Prop 50 gerrymander passed. Meet the rural California republicans who will now be represented by a Marin County progressive.