LANGLEY PARK, Md. (AP) — One the eve of early voting in a close Democratic primary for Maryland governor, Rushern Baker announced Wednesday the endorsement of Valerie Ervin, who abruptly ended her own campaign for the nomination to add more progressive flavor to the campaign of the Prince George’s County executive.

Recent polls have put Baker in a statistical dead heat with former NAACP President Ben Jealous, who has been running as a staunch progressive in a heavily Democratic state with notable endorsements from U.S. Sens. Bernie Sanders, Cory Booker and Kamala Harris. Jealous announced that Sanders will stump for him Monday in Silver Spring.

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Baker, a two-term chief executive from Maryland’s second most populous county, spoke of the endorsement from the first black woman ever elected to the Montgomery County Council to contrast their experience as elected officials with an opponent who has never held elected office.

“The difference between their progressive agenda and our opponent’s is that they’ve actually done the work,” Baker said of Ervin and her running mate, Marisol Johnson, who also attended the announcement. “They haven’t just talked about it.”

Baker has won endorsements from statewide-elected officials, including U.S. Sen. Chris Van Hollen and Attorney General Brian Frosh. On Wednesday, Montgomery County Executive Isiah Leggett, who leads Maryland’s most populous county with more than 1 million residents, attended the announcement.

“We see that this is bringing together a unified force of people who are committed to progressive issues to ensure the betterment for the great state of Maryland,” Leggett said.

Ervin’s candidacy faced difficulties. Her campaign for governor began only last month, after her running mate Kevin Kamenetz died suddenly of a heart attack. Ervin was unable to get the courts to change the ballot to show she was running for governor with her own running mate, who is a former member of the school board Baltimore County. Elections officials said it was too late to change the ballot.

Ervin also was unable to tap Kamenetz’s campaign funds and was hampered by insufficient money for a statewide race. Partly from her court battle, she made headlines in a campaign that lasted less than a month. She said her campaign attracted interest from women, young voters, immigrants and minorities.

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“Our message was a simple one that was absent in the gubernatorial race, and it resonated with this important base of voters in the Democratic primary,” Ervin said. “It came from a belief in a future that not only includes them, but a future that builds upon the incredible diversity that we all know makes Maryland great.”

Maryland’s Democratic primary is a crowded one with nine candidates on the ballot, but polls have shown Baker and Jealous are the clear front runners.

Jealous, meanwhile, released an economic agenda on Wednesday aimed at raising wages, battling unemployment and underemployment and expanding rural broadband. Jealous also is calling for the creation of a new Governor’s Office of Tech Transfer to support small businesses and startups in the tech industry.

Early voting begins Thursday and runs through next Thursday. Maryland’s primary is June 26.

Gov. Larry Hogan, a Republican, is unchallenged in the GOP primary.

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