WASHINGTON — California’s state Senate leader Kevin de León said on Sunday he would run for U.S. Senate in a bid to unseat fellow Democrat Dianne Feinstein, who announced just last week that she would seek reelection next year. His announcement sets up a potentially bitter generational battle between Feinstein, 84, one of the Senate’s most senior Democrats, and de León, 50, who is the California Senate president pro tem and who represents east Los Angeles. “We now stand at the front lines of a historic struggle for the very soul of America, against a President without one,” de León said in a video statement to supporters on Sunday. Feinstein announced on Monday that she would seek re-election to a sixth term, writing on Twitter, “Lots more to do: ending gun violence, combating climate change, access to healthcare. I’m all in!” But even though she has sailed to victory in her most recent campaigns against nominal opposition, she has become a target on the left among activists who see her as too moderate on issues like health care and not strident enough in criticizing President Donald Trump. Soon after de León announced his bid, one group, Democracy for America, gave their endorsement. Kevin de León to Challenge Dianne Feinstein for Senate Seat It's over.