As of March 9, 2,625 major party candidates have filed to run for the Senate and House of Representatives in 2020.

So far, 377 candidates are filed with the Federal Elections Commission (FEC) to run for U.S. Senate in 2020. Of those, 318—165 Democrats and 153 Republicans—are from one of the two major political parties. In 2018, 527 candidates filed with the FEC to run for U.S. Senate, including 137 Democrats and 240 Republicans.

For U.S. House, 2,546 candidates filed with the FEC to run for U.S. House in 2020. Of those, 2,307—1,090 Democrats and 1,217 Republicans—are from one of the two major political parties. In 2018, 3,244 candidates filed with the FEC, including 1,566 Democrats and 1,155 Republicans.

On March 6, President Donald Trump announced he was appointing Rep. Mark Meadows (R-N.C.) as White House chief of staff. Meadows will be the ninth member of the 116th Congress to leave office early. He had announced in December that he would not seek re-election.

In addition to the above nine early departures, 36 members of the U.S. House are not seeking re-election in 2020—27 Republicans and nine Democrats. Four senators (three Republicans and one Democrat) are not running for re-election. In 2018, 55 total members of Congress—18 Democrats and 37 Republicans—did not seek re-election.

On November 3, 2020, 35 Senate seats and all 435 House seats are up for election. Of those Senate seats, 33 are regularly scheduled elections, while the other two are special elections in Arizona and Georgia. Twelve are Democratic-held seats and 23 are Republican-held seats. In the House, Democrats currently hold a majority with 232 seats.