© Greg Nash
Former Democratic presidential candidate Martin O'Malley is throwing his support behind Rep. Chris Van Hollen, a day before Tuesday's Democratic Senate primary in Maryland.
"I stood with Barbara MikulskiBarbara Ann MikulskiHarris invites every female senator to dinner next week Will the real Lee Hamiltons and Olympia Snowes please stand up? Bottom line MORE in her historic campaign for U.S. Senate in 1986, and I’m standing with Chris tomorrow on election day," O'Malley, who worked on the retiring Democratic senator's campaign 30 years ago, wrote to supporters on Monday.
"I hope you will join me in voting for a progressive who will get things done for the state we love," O'Malley added.
Van Hollen held a 6-point lead over Democratic primary rival Rep. Donna Edwards in a poll released earlier this month.
Van Hollen has been seen as the establishment favorite in the heated primary race, securing Senate Minority Leader Harry ReidHarry Mason ReidTo Build Back Better, we need a tax system where everyone pays their fair share Democrats say Biden must get more involved in budget fight Biden looks to climate to sell economic agenda MORE's (D-Nev.) endorsement early last year, while Edwards has been backed by several high-profile progressive groups and figures.
O'Malley, the former governor of the state who ran unsuccessfully for the 2016 Democratic presidential nomination, praised Van Hollen's record on gun control, education and environmental issues.
"In my time serving on the Baltimore City Council, as Mayor of Baltimore, and as Governor, Chris was a reliable, progressive partner in the General Assembly and in Congress," O'Malley wrote.
"At this critically important time for Maryland and our country, we need a progressive U.S. Senator who is able to deliver results for our great state and to move the nation forward," O'Malley added. "That progressive is Chris Van Hollen, and I’m urging you to support him in the primary tomorrow."
O'Malley has declined to weigh in on another Democratic primary that Maryland voters will vote on Tuesday: the presidential race.
O'Malley told MSNBC earlier this month in his first television interview since ending his own White House bid that he wouldn't be endorsing in the Democratic presidential primary between former Secretary of State Hillary ClintonHillary Diane Rodham ClintonDemocrats worry negative images are defining White House Heller won't say if Biden won election Whitmer trailing GOP challenger by 6 points in Michigan governor race: poll MORE and Sen. Bernie SandersBernie SandersDo progressives prefer Trump to compromise? Texas House Republican tests positive for coronavirus in latest breakthrough case In defense of share buybacks MORE (I-Vt.).