Former House Speaker Nancy Pelosi endorsed fellow Democratic Rep. Adam Schiff on Thursday in his 2024 bid for the seat now held by Sen. Dianne Feinstein, providing the long-serving incumbent doesn’t seek a seventh term.

The public blessing of Schiff’s candidacy, though conditional, was significant. Feinstein has said she will make a decision about her future in the next couple of months. But Pelosi’s announcement represented the strongest signal to date that it’s unlikely Feinstein — at 89 the oldest member of Congress — will run again.

The endorsement gives the Southern California congressman the support of one of the most powerful Democrats in the country in what is expected to be a highly competitive race, and signals to Pelosi’s vast donor network that he is her choice for the job.

Neighbors in San Francisco, Pelosi and Feinstein are personally close and have worked together for decades in Washington, suggesting her decision to back Schiff early in the campaign also carried with it a tacit nod from the senator.

If Feinstein decides to seek re-election “she has my whole-hearted support,” Pelosi said in a statement. If not, she said she will support Schiff, who rose to national prominence as the lead prosecutor in President Donald Trump’s first impeachment trial.

Schiff “knows well the nexus between a strong democracy and a strong economy,” said Pelosi, who tapped him for the impeachment position.

It also was unusual to see Pelosi pick sides in a contest expected to draw a crowd of rival candidates from within her own party. Democratic Rep. Katie Porter entered the race for the safe Democratic seat last month. Other possible contenders include Democratic Rep. Barbara Lee, a former chair of the Congressional Black Caucus.

Feinstein’s reticence about her future has created a publicly awkward dynamic — the Senate race to replace her is unfolding, even as the senator remains unclear about her intentions.

In recent years, questions have arisen about her cognitive health and memory, though she has defended her effectiveness in representing a state that is home to nearly 40 million people.

Pelosi’s support for Schiff was not surprising. They have worked together for years and are close. Porter, a leader in the party’s progressive wing who was first elected in 2018, ran as an outsider looking to shake up the Washington status quo. She has had occasional breaks with Democratic leadership, including her opposition to the revival of so-called earmarks, or spending for legislators’ home-district projects.