WASHINGTON — Representative Katie Porter, a third-term California Democrat who studied under Elizabeth Warren at Harvard University and became a social media darling of liberal Democrats, said Tuesday that she would run in 2024 for the Senate seat held by Dianne Feinstein.
Ms. Porter, 49, is the first announced challenger to Ms. Feinstein, 89, who has not declared her intentions about 2024 but is widely expected to not seek re-election amid Democratic worries about her age and ability to serve. Last year, Ms. Feinstein declined to serve as president pro tem of the Senate and earlier relinquished her post as the top Democrat on the Senate Judiciary Committee under immense pressure after the Supreme Court confirmation hearing of Justice Amy Coney Barrett.
“It’s time for new leadership in the U.S. Senate,” Ms. Porter said in a video announcing her campaign.
Ms. Feinstein, in a statement released by her office, said she would “make an announcement concerning my plans for 2024 at the appropriate time.” She said she was focused on addressing the deadly storms battering California.
Ms. Porter’s early campaign announcement — which carries echoes of Ms. Warren’s entrance to the 2020 presidential contest, when she was the first major Democrat to embark on a bid — jump-starts a race that is certain to be among the most expensive intraparty contests in the country. A vaunted fund-raiser, Ms. Porter became widely known for her combative treatment of witnesses from the financial sector and Trump administration officials who appeared before her on the House Oversight Committee.
The Iowa-born Ms. Porter was a leading surrogate for Ms. Warren’s 2020 campaign and often hosted small events promoting her mentor. She worked as a law professor at the University of California, Irvine, and in 2012 was appointed by Kamala Harris, then the California attorney general, to oversee a $9 billion settlement after the mortgage crisis. She was elected to Congress in 2018.
Ms. Porter won re-election in November by 3.4 percentage points in a district made much more Republican in California’s redistricting process, after prevailing in 2020 by seven points. Her seat may be tougher for Democrats to hold in 2024 without a candidate on the ballot who has Ms. Porter’s fund-raising acumen.
Other California Democrats who have not announced campaigns for Ms. Feinstein’s Senate seat but are believed to be considering bids include Representative Adam Schiff, who has already hired staff members in preparation for a statewide campaign; Representative Barbara Lee, who has told donors of her plans to run; and Representative Ro Khanna, an aide for whom said Mr. Khanna would decide on the Senate race “in the next few months.”
“It’s going to be a very exciting race with fabulous people — several have already talked to me,” said former Senator Barbara Boxer, a California Democrat who served for four terms alongside Ms. Feinstein before retiring in 2016. “The fact that Katie Porter has announced, I think, is going to open the door for a lot of early announcements.”
California, the nation’s most populous state with nearly 40 million residents, has not hosted a highly competitive contest for an open Senate seat since 1992, when Ms. Feinstein and Ms. Boxer were both elected for the first time.
Ms. Feinstein, in her sixth term, has been dogged by questions about her fitness to serve. Issues with her short-term memory have become an open secret on Capitol Hill, though few Democrats have been willing to discuss the subject publicly.
She has made no moves to suggest she will seek re-election in 2024. She has not hired a campaign staff and, in the latest campaign finance report for the period ending in September, had less than $10,000 in cash on hand, a paltry sum for a sitting senator.