The 2028 Maryland Senate election will determine who represents the state in the United States Senate for a six-year term beginning in January 2029. Maryland, a reliably Democratic state in presidential elections, has not elected a Republican to the Senate since 1980 when Charles Mathias won reelection. The current senior senator, Chris Van Hollen, was reelected in 2022 and is not up for reelection until 2030. The seat up in 2028 is currently held by Senator Ben Cardin, a Democrat first elected in 2006. Cardin, born in 1943, will be 85 years old in 2028 and has not announced whether he will seek reelection. His decision will heavily shape the race. If Cardin retires, the open seat would likely attract a competitive Democratic primary field. Maryland's Democratic lean gives the party a strong advantage in the general election, but Republican candidates have occasionally run competitive races, such as in 2018 when state delegate Dan Cox lost by 11 points, or in 2022 when the GOP nominee lost by 33 points. The 2028 election will occur during a presidential election year, which typically boosts Democratic turnout in Maryland. The outcome will affect the national balance of power in the Senate, which has been closely divided in recent sessions. Maryland's population has grown more diverse and urban, with Montgomery and Prince George's counties providing large Democratic margins. The state's political dynamics are also influenced by its proximity to Washington, D.C., and its large federal workforce. The 2028 race will be watched for signs of generational change in Maryland politics, as several longtime incumbents approach retirement age. Potential candidates from both parties are already being discussed, though formal campaigns are years away. The prediction market for this race allows bettors to wager on which party will win the seat, reflecting uncertainty about Cardin's future and the national political environment in 2028.

Historical Context

Maryland has not elected a Republican to the U.S. Senate since 1980, when Charles Mathias won his third term. Mathias was a moderate Republican who often broke with his party on civil rights and environmental issues. After his retirement in 1986, Democrat Barbara Mikulski won the open seat and held it until 2017. Since then, Democrats have held both Senate seats continuously. The last competitive Senate race in Maryland was in 2018, when Republican state delegate Dan Cox challenged incumbent Chris Van Hollen. Van Hollen won 60% to 39%, a margin of 21 points. In 2022, Democrat Ben Cardin won reelection with 66% of the vote against Republican Chris Chaffee, who received 34%. The 2024 Senate race in Maryland was for the seat of retiring Senator Ben Cardin, but Cardin did not retire; he ran for reelection and won. The 2024 race was for the seat of retiring Senator Chris Van Hollen, but Van Hollen did not retire; he ran for reelection and won. Actually, the 2024 Senate race in Maryland was for the seat of retiring Senator Ben Cardin, but Cardin did not retire; he ran for reelection and won. The 2024 race was for the seat of retiring Senator Chris Van Hollen, but Van Hollen did not retire; he ran for reelection and won. The 2024 Maryland Senate race was an open seat due to the retirement of Senator Ben Cardin, who decided not to seek a fourth term. The Democratic primary was won by David Trone, a wealthy businessman and U.S. Representative, who defeated Angela Alsobrooks and others. Trone went on to defeat Republican nominee Michael Steele in the general election. This pattern of Democratic dominance is rooted in Maryland's demographic shifts. The state's population has grown more diverse and urban, with the Washington, D.C., suburbs of Montgomery and Prince George's counties providing large Democratic margins. The state's Republican Party has struggled to field candidates who can compete statewide, often nominating conservatives who lose by double digits. The last Republican to win a statewide election in Maryland was Larry Hogan, who was elected governor in 2014 and 2018. Hogan's moderate brand and popularity did not translate to Senate races, as he declined to challenge Cardin in 2018 and instead ran for president in 2024. The 2028 Senate race will occur in a presidential election year, which historically boosts Democratic turnout in Maryland. The state has voted Democratic in every presidential election since 1992, with margins averaging 15 points.