Maryland Rep. Donna Edwards today endorsed businessman John Delaney in the 6th district race, putting her on the opposite side of three of her fellow Democratic colleagues.

While it does not carry the stature of a national endorsement from President Bill Clinton, Edwards’ support has strategic and symbolic resonance of its own.

Delaney is facing state Senate Majority Leader Rob Garagiola in what has become a tough Democratic primary. The 6th district was essentially redrawn with Garagiola, who is deeply entrenched with Maryland Democratic insiders, in mind. House Minority Whip Steny Hoyer is backing Garagiola, along with Reps. Elijah Cummings and Dutch Ruppersberger.

Edwards, who defeated an incumbent in a primary, is still more of an outsider and unafraid to challenge conventional thought.

“It’s a big deal,” a plugged-in Maryland Democrat said of the endorsement. “And it’s a pretty big shot at Steny and Annapolis.”

Grass-roots activists and labor union members are passionate Edwards backers. Garagiola had been making inroads with grass-roots groups, gaining endorsements from the likes of MoveOn.org. His backers have made a concerted effort to portray Delaney as anti-union and as a Republican in sheep’s clothing. But Edwards’ liberal credentials will likely give Delaney cover on that flank.

The Edwards endorsement occurred this morning during rush hour at the Shady Grove Metro Station in suburban Maryland.

“I am proud to support John Delaney to represent Maryland’s 6th Congressional District in Congress,” she said in a statement. “John has the intellect, independence, and core values to be a true leader in Congress.

The winner of the Democratic primary will likely face Rep. Roscoe Bartlett (R), who noted in a recent interview that he and Edwards share a warm relationship despite their partisan differences.

Roll Call rates the race as Leans Democratic.