"I'm so honored to pass the baton to you," Lee said in a video message. "Let us continue to stand up for the values of the 12th Congressional District and continue building a broad coalition, working together for a better world."

Simon, who will represent Alameda County after Lee leaves office following 26 years in Congress, told KQED she is prepared to do just that.

"We have to fight like hell," she said Thursday. "To ensure that the people of the United States have health care, that we push back on the Trump administration's promise to gut Social Security. Women like my children, my girls, do not have the right to pursue bodily autonomy in the state of this country."

The Associated Press hadn't officially called the race as of Thursday afternoon, but with about a quarter of the votes counted so far, Simon is leading fellow Democrat Jennifer Tran with 63%. Simon said the House administration had already reached out to arrange travel to its freshman orientation next week.

When she arrives on Capitol Hill, Simon said she'll focus not only on guarding against the Trump administration's likely extreme policies but also on public transportation and safety -- policy areas she's been influencing in her home state for years. She is a former president of the BART board, which she has sat on since 2016, and served as co-chair of Gov. Gavin Newson's police reform task force in 2020.