This article is from the archive of our partner National Journal

When Sen. Barbara Mikulski, the longest-serving woman in congressional history, announced that she was stepping down next year, a diverse cast of contenders emerged for her Senate seat. Rep. Donna Edwards, who would be the first African-American woman to represent Maryland in the Senate and only the second in the upper chamber's history, was quick to indicate her interest in the race. And Baltimore Mayor Stephanie Rawlings-Blake said she would take a look at the seat as well.

But four days later, Senate Minority Leader Harry Reid announced he was supporting a white man—Rep. Chris Van Hollen—to replace her.

Mikulski was furious, Democratic sources say. The Maryland Democrat has decided not to endorse in the race and was stunned that Reid barged in, particularly with two promising female candidates eyeing the race. (Edwards officially entered just days after Reid announced his endorsement.)

The feeling among Democratic activists in the state—as well as national groups eyeing the race—is that the primary is likely be a bloody one.

(RELATED: Mikulski's Retirement Unleashes Democratic Domino Effect in Maryland)

Mikulski likes Edwards personally and the two have worked closely together to advance Maryland's interests, a Senate Democratic aide said. Van Hollen, not so much. And as a major proponent of closing the gender gap in the Senate, where just 20 members are women, Mikulski would like to see the seat go to a female candidate; though she plans to let voters make that decision themselves. "I think it's important for Maryland to make a choice that they are crazy about," Mikulski said.

Progressives and women's advocacy groups centering in on the open Democratic seat were floored by Reid's endorsement. "When Maryland has a chance to break a glass ceiling in terms of electing the first African-American woman, it was a really bizarre decision for the leader of the Democratic Party to come out for someone who couldn't break that ceiling," said Neil Sroka, communications director for Democracy for America, which is backing Edwards. "It was just a really weird move."

EMILY's List, which gave its first-ever endorsement to Mikulski in 1986, also threw its support behind Edwards Thursday morning (a sign Rawlings-Blake will take a pass on the race). And the group questioned the efficacy of Reid's backing—and flagged a lack of diversity among Van Hollen's early supporters.

"[Van Hollen's] first couple of endorsements, they were all like white men. He didn't have a lot of diversity when he was starting to roll out his campaign," an EMILY's List spokeswoman said, noting that the Democratic Senatorial Campaign Committee is not getting involved in the race. "I'd be very curious how a Reid endorsement actually plays in the state of Maryland. "¦ It's probably a Beltway strategy, probably helps to raise some money."

"[It's] just kind of a strange move on Van Hollen's part. Like, keep it local dude. I understand this is how you lock down donors, but it just seemed a little tone deaf," one national progressive activist said.

A Van Hollen ally noted that Montgomery County Executive Ike Leggett, an African-American, was one of the congressman's first endorsements. And the entire Montgomery County Council, which includes two women and an African-American, followed closely after Reid.

(RELATED: Chris Van Hollen Will Run for Mikulski's Maryland Senate Seat)

Edwards's own campaign isn't being shy about playing those endorsements off of each other. In a fundraising email titled "Endorsements Rolling In" sent to supporters Thursday, Edwards's team wrote: "EMILY's List was there 30 years ago to help Senator Barbara Mikulski conquer the old boys' network and make national history right here in Maryland."

Van Hollen, however, has his own strong ties within the Democratic Party, and a long, tight relationship with Reid. The two worked closely together on the (failed) Super Committee, on the fiscal-cliff deal at the end of 2012, on the Iraq War resolution, and on other major issues. Reid was blown away by the young congressman from Maryland, and he has been impressed by his work on the House Budget Committee as well.

When Reid heard Van Hollen was running for the Senate, he saw a potential ally. An establishment Democrat with the war chest to win the seat, sure. But also a deal-maker with experience getting things done and working to advance the Democratic economic message.

Edwards has also made some enemies within the party establishment over the years, particularly within Maryland, and her history suggests she's more likely to be a thorn in leadership's side. But Reid spokesman Adam Jentleson said the leader's endorsement was in no way a knock on Edwards, or on any other potential candidate for the seat.

And despite concerns from progressive activists, Jentleson said Reid was not trying to avoid a primary, either. The endorsement was about loyalty to a longtime friend and colleague, not an attempt to keep others out of the fray.

Reid's frayed relationship with progressives has been mended in recent months. But it was just last November when Reid appointed Sen. Elizabeth Warren to leadership, to stave off an insurrection from members in the party's ideological left and right wings, some of whom went so far as to oppose his bid for minority leader.

"The best progressive Democrats are the ones that are willing to step up and confront leaders when it's necessary," Sroka said, noting that Edwards has done that time and again in the House. In that sense, he argued, the Reid endorsement could work against Van Hollen with progressives. "She's not one that's currying favor with the leadership,"

Regardless, Maryland Democrats don't believe that the endorsement from Reid, a Nevadan, will have much of an effect on the race. Although Democrats concede that the high-profile endorsement could help Van Hollen to raise money early in the race, it clearly hasn't narrowed the field. Along with Van Hollen and Edwards, Reps. Elijah Cummings, John Delaney, and John Sarbanes are all still looking at the race.

"There's not going to be a clear field in Maryland for the Senate race," said Maia Estes, former Lt. Gov. Anthony Brown's chief of staff. "The only endorsement that could really clear the field is Sen. Mikulski."

This article is from the archive of our partner National Journal.

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