Here Are the Top Senate Primary Contests to Watch for 2026

Five states will have competitive primary elections, three of which are safe seats for either party. Races in Georgia and Michigan could determine the majority.

Senate Majority Leader Chuck Schumer (2nd R) (D-N.Y.) attends a bipartisan meeting with (L-R) Sen. John Thune (R-S.D.), Senate Minority Leader Mitch McConnell (R-Ky.), and Sen. Dick Durbin (D-Ill.) at the U.S. Capitol in Washington on July 21, 2021. Win McNamee/Getty Images

WASHINGTON—After just five months of the 119th Congress, elections to the 120th Congress to be held in 2026 are on the horizon. Already, several longtime U.S. senators have announced their retirement at the end of this Congress, prompting several contenders to announce their candidacies.

The primary elections for Senate seats—the first step in the process, where parties will determine their nominees for the general election—are expected to be hotly contested. Given that many of the states involved are safely governed by one party, i.e., “red” or “blue” states, as opposed to battlegrounds, a victory in the primary entails a likely victory in the general election and the possibility of long service in the Senate.

Kentucky’s Republican Primary

One of the longest-serving members of the Senate, Mitch McConnell (R-Ky.), is retiring. McConnell was first elected to the Senate in 1984, and was elected as the Leader of the Senate Republican Conference in 2007. He assumed the office of Senate Majority Leader in 2015, after Republicans won a majority in the 2014 midterms, and held that role for the entirety of President Donald Trump’s first term.

McConnell’s retirement, long anticipated, opens up a Senate seat in a safely Republican state. The likelihood of a GOP victory is compounded by the decision of Kentucky Gov. Andy Beshear (D) to not run in the Senate election, ahead of a possible presidential campaign in 2028.

Currently, former state Attorney General Daniel Cameron (R) is running in the primary. Cameron is a McConnell protégé, having run in the 2023 gubernatorial election against Beshear with McConnell’s endorsement. Against him is Rep. Andy Barr (R-Ky.).

Barr has picked up the endorsements of three of his House colleagues: Majority Leader Steve Scalise (R-La.), former Conference Chair and Rep. Elise Stefanik (R-N.Y.), and Rep. Hal Rogers (R-Ky.).

In safely Republican states, the endorsement of Trump is often the decisive factor in the primary contest. Trump endorsed Cameron’s gubernatorial run in 2023 but has not announced his choice in the Senate race.

A recent poll shows Cameron leading the primary race with 44 percent support.

Illinois’s Democratic Primary

In Illinois, another big retirement has shaken up the race. Senate Minority Whip Dick Durbin (D-Ill.) is retiring after the 119th Congress after nearly 30 years of service in the Senate, and over 40 years of cumulative service in Congress. Illinois contains the City of Chicago, one of America’s largest and most progressive cities, and the seat is both safely Democratic as well as a prominent springboard for national office. Former President Barack Obama began his career in federal office as a senator from Illinois in 2005 and was elected to the presidency merely three years later in 2008.

The Democratic Primary in Illinois has already invited contestants. The state’s lieutenant governor, Juliana Stratton (D), has announced her candidacy, and two Democratic members of Congress from the state, Reps. Raja Krishnamoorthi and Robin Kelly, have also entered the race.

Kelly, at present, is the leader in endorsements, with over a dozen from her Democratic colleagues in the House. Stratton, by contrast, has earned the endorsement of Gov. J.B. Pritzker (D), who has declined to run amid speculation that he may run for president in 2028. Stratton has also been endorsed by Sen. Tammy Duckworth (D-Ill.), the state’s other U.S. senator.

In terms of polling, Stratton was the leader in the race until Krishnamoorthi’s entry. The latest poll by Public Policy Polling shows Krishnamoorthi ahead with 20 percent support.

Michigan’s Democratic and Republican Primary

In Michigan, Sen. Gary Peters (D-Mich.) is retiring from the Senate after two terms of service. Michigan is a presidential battleground state in quadrennial general elections, making it a prominent springboard for higher office.

As a result, the primary elections for both parties are contested closely. The Democratic Primary already has four candidates in the race: former gubernatorial candidate Abdul El-Sayed, state Sen. Mallory McMorrow, U.S. Rep. Haley Stevens, and former state House speaker and state Rep. Joe Tate.

No major polling has been conducted with all four candidates, though endorsements signal the different factions of the party that they may court. El-Sayed has been endorsed by prominent progressives such as Sen. Bernie Sanders (I-Vt.) and Rep. Ro Khanna (D-Calif.). Stevens, by contrast, has been endorsed by the American Israel Public Affairs Committee (AIPAC), a prominent pro-Israel lobby group in the United States.

In the Republican primary, there is only one candidate: former Rep. Mike Rogers (R-Mich.), who was the GOP’s nominee in the Senate election in 2024, a race he lost to then-Rep. and now-Sen. Elissa Slotkin (D-Mich.). Rogers earned Trump’s endorsement in 2024, but other prominent politicians are reportedly considering running, such as Rep. Bill Huizenga (R-Mich.) and former gubernatorial nominee Tudor Dixon.

Minnesota’s Democratic Primary

In Minnesota, Sen. Tina Smith (D-Minn.) is retiring from the body after seven years of service. She was appointed to the Senate in 2018 after the resignation of Sen. Al Franken (D-Minn.) amid a sexual harassment scandal. Smith’s short service, and Minnesota’s progressive lean, means that the state’s Democratic primary will be an important contest.

Presently, three women candidates are running for the Democratic nomination: Lt. Gov. Peggy Flanagan, U.S. Rep. Angie Craig, and former state Senate Minority Leader Melisa Lopez Franzen.

The candidates have been lapping up endorsements from many prominent Democratic figures. Flanagan, the frontrunner, has been endorsed by Franken, Sen. Elizabeth Warren (D-Mass.), as well as the state’s attorney general and auditor, which are statewide elected offices. Craig, by contrast, has earned the endorsement of moderates in the party, such as Rep. Ritchie Torres (D-N.Y.) and former Democratic presidential candidate and former Rep. Dean Phillips (D-Minn.).

Georgia’s Republican Primary

Georgia, another presidential battleground, is the only competitive race where an incumbent senator is seeking reelection. Sen. Jon Ossoff (D-Ga.) was elected in 2020 amid a hotly contested presidential race, which then-nominee Joe Biden won by just over 11,000 votes. In the subsequent presidential election of 2024, the state was won by Trump. Republicans believe Georgia to be among their most likely pickup opportunities in 2026.

With Ossoff as the presumptive Democratic nominee, attention has turned to the Republican primary. However, many prominent conservatives in Georgia have declined to enter the race. Gov. Brian Kemp (R-Ga.) and Rep. Marjorie Taylor Greene (R-Ga.)—the state’s two most prominent GOP politicians representing moderate and populist wings of the party—have both declined to run.

Currently, U.S. Rep. Buddy Carter (R-Ga.) and the state’s Insurance Commissioner John King are running for the Republican nomination. However, without Kemp or Greene, polling shows that the most popular Republican candidate is U.S. Rep. Mike Collins (R-Ga.), who has not entered the race.