Democratic representative Katie Porter, the progressive former law professor known for her sharp questioning of witnesses and her use of a whiteboard during hearings, said she will seek the California Senate seat currently held by Dianne Feinstein.

Feinstein, a fellow Democrat, is the oldest member of the chamber, and has not yet said if she will retire.

“Especially in times like these, California needs a warrior in Washington,” Porter said in a video posted on Twitter. “That’s exactly why I’m announcing my candidacy for the United States Senate in 2024.”

Porter was first elected to Congress in 2018 and won a tight race for re-election to her newly redrawn southern California district in November. She said in the video that she had “challenged the status quo” in Washington, taking on “big banks,” Wall Street and the pharmaceutical industry. She wants to ban members of Congress from stock trading.

“To win these fights, it’s time for new leadership in the US Senate,” she said.

Feinstein, 89, has faced questions about her age and memory and whether she will seek another term. She has not announced whether she will seek re-election in 2024, though she is widely expected to retire.

“Everyone is, of course, welcome to throw their hat in the ring, and I will make an announcement concerning my plans for 2024 at the appropriate time,” Feinstein said in a statement on Tuesday. She added that she is currently “focused on ensuring California has all the resources it needs” to deal with deadly storms hitting the state.

Feinstein won her sixth election in 2018 and has been a force for Democrats, serving for a time as chair of the intelligence and judiciary committees. But she also has seen pushback from Democrats who view her as too bipartisan at a time when politics is more polarized and her state is increasingly liberal.

In 2020, Feinstein announced she would step down as the top Democrat on the Senate judiciary committee. The move followed criticism that she was too friendly with Republicans during supreme court confirmation hearings for Amy Coney Barrett. That included an embrace of the Republican chairman, Senator Lindsey Graham of South Carolina, at the conclusion of the hearings and kind words for what she called a job well done.

Feinstein has defended her performance and said in 2021 that she planned to serve her full term, even as there was open speculation and discussion about the future of the seat. Governor Gavin Newson said in 2021 that he would appoint a Black woman to replace Feinstein, who is white, if she were to retire early.

Porter, 49, was a consumer protection attorney before her election to the House, and she has earned a reputation for her tough questioning of chief executives and other witnesses at congressional hearings – often using a whiteboard to break down information.

Porter’s media savvy was again on display during the recent meltdown in the US House over the election of a new speaker. As Republicans argued, Porter was seen sitting in the chamber, disinterestedly, reading a book on “the subtle art” of not caring about what’s happening.