Balance of Power: A Partisan Convergence in the Senate

Updated as of December 3, 2021

What is the balance of power in the Senate?

Following the success of Democrats Jon Ossoff and Raphael Warnock in two Georgia runoff elections on Jan. 5, 2021, the 2020 election cycle left the balance of power in the Senate evenly split between the parties. The 50-50 divide makes Vice President Kamala Harris the tie breaker.

[Your essential toolkit for government affairs: Find out the six things you need to know to stay on top of legislative developments and connect with policy makers and their staff.]

Senate balance of power

What was the outlook prior to the 2020 election?

The top Democratic targets were Maine and Colorado, the only two states Trump lost in 2016 where Republicans are defending Senate seats in 2020.

Sen. Susan Collins, a politically dominant figure in Maine for a generation, sought a fifth term, while Sen. Cory Gardner ran for his second. Collins held onto her seat, beating Maine House Speaker Sara Gideon. In Colorado, however, former Gov. John Hickenlooper won Gardner’s seat.

The Democratic Senatorial Campaign Committee, the campaign arm of Senate Democrats, also endorsed candidates against Republican incumbents in states that backed Trump by modest margins in 2016. Democrats were successful in Arizona, where gun control activist and former astronaut Mark Kelly came out on top over Sen. Martha McSally. Republican incumbents Joni Ernst, in Iowa, and John Cornyn, in Texas, held onto their seats. In North Carolina, Republican Sen. Thom Tillis eked out a win over Democrat Cal Cunningham, who was recently the subject of a scandal involving sexually suggestive text messages.

[For more BGOV coverage of the 117th Congress, explore our resources page here.]

Most of the rest of the Republican seats at stake in 2020 were out of reach for the Democrats. In 15 of the 23 contests where Republicans had Senate seats on the ballot, Trump carried those states in 2016 by at least 14 percentage points.

Democrats sought to defend two seats in states Trump won in 2016 – Alabama and Michigan. In Alabama, former Auburn coach Tommy Tuberville defeated incumbent Doug Jones. Democrat Jones won the seat in a 2017 special election.

In Michigan, which Trump narrowly won in 2016 and lost in 2020, Democratic Sen. Gary Peters won a second term in a tight race against well-funded businessman and military veteran John James.

[Learn more about how Bloomberg Government helps you track regulatory developments and changes in key legislation – and discover the link between policy and intelligence.]