Sen. Dianne Feinstein passed away Friday morning at the age of 90 following a groundbreaking career in politics. After holding her seat in the Senate since 1992, her colleagues must now seek a replacement.

As Feinstein was a California Senator, it is now up to Gov. Gavin Newsom to appoint someone to fill her seat until the next election, which is in 2024. Feinstein had planned to retire at the end of the current term, leaving an ongoing primary with candidates vying for her seat.

Newsom has previously spoken at length about Feinstein's possible replacement, stating earlier this year that he would appoint a Black woman to a vacancy in the Senate should one open up. Following Vice President Kamala Harris' election, there are currently no Black women in the Senate.

However, Newsom backtracked those comments earlier this month, stating he would only appoint a caretaker to the Senate seat, as he does not wish to disrupt the ongoing primaries by favoring one candidate over another.

Who will replace Feinstein?

In Washington D.C., Democrats now have a 50-49 majority in the Senate, including the three independent senators that caucus with them. It is unlikely losing one vote will be immediately detrimental to the party — the difficulty lies in finding replacements for Feinstein's seats on the Senate Judiciary and Intelligence committees.

Senate Majority Leader Chuck Schumer will need the full chamber to approve her replacements, which typically go through uncontested. However, Republicans blocked Democrats from temporarily removing Feinstein from the Judiciary panel earlier this year, because her health struggles delayed some of President Joe Biden's federal judicial nominees.

Republican Sen. Chuck Grassley of Iowa previously told Insider that the party intends to block Democrats from replacing Feinstein on the Judiciary Committee if given the opportunity. A vacancy would make it more difficult to confirm lower-court judicial nominees, as well as Supreme Court justices in the event of one retiring or passing away.

However, in the case of the Supreme Court, Democrats could still force a full vote on a Biden nominee, as that is what occurred when the committee returned a tied vote on Judge Ketanji Brown Jackson. Using a procedural move, Schumer forced Jackson's nomination, and she was later confirmed to the high court.

Lawmakers are currently preoccupied with the impending government shutdown. The deadline to pass a stopgap funding measure is Sept. 30 at midnight, leaving Congress mere hours to break through infighting among the GOP.

For now, Californians have a lot of voting to do. There will be four elections within the next year to determine the fate of Feinstein's seat, as she died over 148 days before the next primary. A special primary election and a special general election will be held alongside the regular primary and general elections.

Democrats from the House of Representatives — Adam Schiff, Barbara Lee, and Katie Porter — are all running for Feinstein's seat. Schiff, a former chair of the House Intelligence Committee who served as one of the House managers during Trump's first impeachment, currently leads.

Lee, a social worker who has served since 1998, has been hailed as a trailblazing lawmaker for Black Americans. Porter went viral during former president Donald Trump's term for using a whiteboard to grill his administration's officials at hearings.