The primary election for Maine’s congressional seats took place on July 14, 2020. The filing deadline to run passed on March 16. Candidates competed to advance to the general election scheduled on November 3.

• U.S. House of Representatives – two seats

Maine uses a ranked-choice voting system (RCV), in which voters rank candidates by preference on their ballots. If a candidate wins a majority of first-preference votes, he or she is declared the winner. If no candidate wins a majority of first-preference votes, the candidate with the fewest first-preference votes is eliminated. First-preference votes cast for the failed candidate are eliminated, and the second-preference choices on those ballots are then tallied. A new tally is conducted to determine whether any candidate has won a majority of the adjusted votes. The process is repeated until a candidate wins an outright majority.

As of July 2020, Maine was the only state that had adopted RCV at the state level, although other states have adopted RCV at the municipal level or have adopted RCV but not yet implemented it.

Maine’s primary election was the 31st to take place in the 2020 election cycle. The next primary is on August 4 in Arizona.

Alabama and Texas held statewide primary runoffs on July 14.

The filing deadline to run in Alabama passed on November 8, 2019. To avoid a primary runoff in Alabama, a candidate had to win a majority of votes cast in the primary election. If no candidate won a majority of votes, the top two candidates advanced to the primary runoff. Alabama’s primary election was held on March 3, 2020. Three congressional seats advanced to primary runoffs in Alabama, including one race for the U.S. Senate and two for the U.S. House. All three of these races were decided on election night.

In Texas, the filing deadline to run for office passed on December 9, 2019. To avoid a primary runoff in Texas, a candidate had to win a majority of the votes in the primary election. If no candidate won a majority of votes, the top two candidates advanced to the primary runoff. Texas’ primary was held on March 3, 2020. Fifteen congressional offices—one U.S. Senate seat and 14 U.S. House seats—advanced to primary runoffs in Texas. All but two of those races were decided on election night.