(CNN) The 117th Congress, being sworn in Sunday, is historically diverse, with record-setting numbers of women, Black and Latino members and members who identify as LGBTQ.
But even as the new Congress begins, its roster will likely remain unsettled for months.
There will be two vacancies in the House: New York's 22nd District will not have representation as legal challenges in the race continue, and Louisiana's 5th District will not have representation due to the death of Republican Rep.-elect Luke Letlow. In the Senate, one of Georgia's Senate seats will be vacant as Republican Sen. David Perdue battles in a runoff for the seat on January 5.
Republican Sen. Kelly Loeffler is also running in Georgia's dual runoff elections Tuesday. Perdue's term finished at the end of the 116th Congress, so he is not included in the new Congress' numbers. Loeffler's term will continue unless she is defeated Tuesday, so she is counted.
In other changes to congressional rosters in the coming weeks, Vice President-elect Kamala Harris will be stepping down from her Senate seat to be replaced by California Secretary of State Alex Padilla.
And in the House, three Democratic members are expected to leave office to take on roles in the new Biden administration: Rep. Cedric Richmond of Louisiana (2nd Congressional District) to be White House senior adviser and director of the Office of Public Engagement; Rep. Deb Haaland of New Mexico (1st Congressional District) to be Secretary of the Interior; and Rep. Marcia Fudge of Ohio (11th Congressional District) to be Secretary of Housing and Urban Development.
Here is a breakdown by numbers of the new Congress as it begins, as well as some notable members who will be sworn into office.
117th Congress membership breakdown by party:
Democrats: 222
Republicans: 211
Vacant: 2 (Louisiana's 5th District and New York's 22nd District)
Freshmen Class: There will be 60 freshmen in the 117th Congress. Seventeen of those seats flipped during the 2020 general election, with Republicans picking up 14 seats and Democrats picking up 3. This resulted in a current net gain of 11 seats for Republicans. Eleven of the Republicans who picked up seats defeated Democrats who flipped seats in the wave year of 2018, while one GOP pickup came from the defeat of long-time Democratic Rep. Collin Peterson of Minnesota, one came in an open seat (Iowa's 2nd) and one was in a Libertarian-held seat (Michigan's 3rd District).
None of the new Democratic House members defeated sitting Republicans.
Freshmen: 60
Total 2020 flipped House districts: 17
Total Women: 118
The 117th Congress will see a record number of women in the House, and a record number of Republican women. Ten of the Republicans who flipped Democratic seats were women.
Total freshmen women: 27
Age of House members:
20s: 1
30s: 30
40s: 82
50s: 122
60s: 123
70s: 63
80s: 12
Republican Madison Cawthorn of North Carolina, born August 1, 1995, will be the youngest member of this Congress at age 25. He takes that title from Rep. Alexandria Ocasio-Cortez of New York who, at 31, is now the chamber's second youngest member. Cawthorn is also the first member of Congress born in the 1990s.
Making House history:
117th Congress Senate breakdown by party:
Republicans: 51 (including Sen. Kelly Loeffler)
Democrats: 48 (including two independents who caucus with the Democrats)
Vacant: 1 (Georgia)
Total new senators: 7
Democrats: 3
Republicans: 4
There will be 7 new senators at the start of 117th Congress, including Democratic Sen. Mark Kelly of Arizona, who was sworn in in December. Three seats flipped during the 2020 general election, with Democrats flipping two and Republicans flipping 1. This resulted in a net gain of 1 seat for Democrats.
Total flipped seats: 3
Democrat: 2
Republican: 1
Total women: 26 (will decrease to 25 when Padilla replaces Harris)
Democrat: 17
Republican: 9
Total new female senators: 1
Democrat: 0
Republican: 1
Total states with two female senators: 5 (will decrease to 4 when Padilla replaces Harris)
Democrat: 5
Republican: 0
Age of senators
30s: 0
40s: 11
50s: 20
60s: 42
70s: 21
80s: 5
Republican Sen. Josh Hawley of Missouri, born on December 31, 1979, remains the Senate's youngest member at 41. The youngest new senator is Ben Ray Lujan of New Mexico, a Democrat, at 48.
Making Senate history:
Total Black members in the House and Senate: 61
House: 58 (56 Democrats, 2 Republicans)
Senate: 3 (2 Democrats, 1 Republican) (will decrease to 2 when Padilla replaces Harris)
The 117th Congress will have the largest number of Black members in the history of the House and in the history of Congress. The 58 representatives are a new record for the House, while the record-high three in the Senate remains the same, at least until Harris resigns to become vice president.
Total Latino members in the House and Senate: 44
House: 39 (30 Democrats, 9 Republicans)
Senate: 5 (3 Democrats, 2 Republicans) (will increase to 6 when Padilla replaces Harris)
The 44 Latino members of Congress will be the most ever, according to NALEO. There will also be the most ever Latino senators. Latino House membership will match the current record high. The overall record total in Congress will increase to 45 when Padilla replaces Harris.
Total LGBTQ members in the House and Senate: 11
House: 9 (9 Democrats, 0 Republican)
Senate: 2 (2 Democrats, 0 Republican)
According to LGBTQ Victory Institute, this will be the most people who identify as LGBTQ to ever serve in the House and the most to ever serve in Congress.
Total veteran members in the House and Senate: 91
House: 74 (21 Democrats, 53 Republicans)
Senate: 17 (7 Democrats, 10 Republicans)
Fourteen newly elected veterans will be joining the House this year, according to the University of San Francisco and the Veterans Campaign. That's down from the 18 veterans who were first elected in 2018, but up slightly from the three cycles before that.
Retiring members in the House and Senate: 3
At least 2 Republican senators and 1 Democratic House member have already announced they will not seek reelection in 2022: