Residents of California's 25th congressional district will cast two primary votes for U.S. House on Super Tuesday, March 3.   Both are top two primaries, meaning all candidates will appear on the ballot.  There are differences on what happens after that.

Special Primary Election:  This begins the process of filling the seat vacated by former Rep. Katie Hill (D) last November.  If one candidate receives a majority of the vote, that person is elected to Congress. Otherwise, the top two finishers will advance to the special general election on May 12.  Given the size of the field, it is unlikely anyone will win outright on March 3.

Regular Primary Election:  This is a primary for the two-year term that will begin in January, 2021. The top two finishers will advance to the general election on November 3. 

Given the timing of these two primaries, an unusual outcome can't be ruled out - although it is unlikely. For example, if the winner of the special election isn't in the top two in the regular primary, that person will be a lame duck as soon as they are seated in Congress.