D.C. Democratic mayoral nominee Muriel Bowser, left, is congratulated by former D.C. mayor Marion Barry, middle, during the Democratic State Committee Unity Breakfast. (Amanda Voisard/The Washington Post)

Three days after District Democrats chose Muriel Bowser over Mayor Vincent C. Gray, more than 200 party leaders huddled Friday in the fellowship hall of a Baptist church in Southeast Washington and gushed over their nominee — with one notable exception.

It wasn’t like when Adrian M. Fenty offered a grand gesture of conciliation four years ago by taking the stage and saying he looked “forward to having Vince Gray as my mayor.” Gray didn’t pass the baton as freely.

Gray never referred to Bowser by name and walked off stage without greeting her. He returned to do so only after being questioned by reporters.

Gray’s behavior aside, the party’s traditional Unity Breakfast amounted to a show of force against D.C. Council member David A. Catania (I-At Large). The 17-year veteran of the council has declared that he will run against Bow­ser, his council colleague from Ward 4, giving Democrats their first real challenge for the mayor’s office in 20 years.

“We fight like cats and dogs,” said D.C. Council member ­Marion Barry (D-Ward 8), who backed Gray but said he “can’t wait” for Bowser to become mayor. “When it’s over, it’s over. We unite, together, as Democrats.”

In an e-mail solicitation for campaign donations, Catania cast the gathering as an attempt by Democrats to revert to partisan politics to prop up a candidate with a thin legislative record.

“They are circling the wagons to keep their hold on our city government,” Catania said, asking for $10 donations to kick off his campaign. “On Tuesday, by staying at home, voters showed that they want something different this year. They want a leader who shares their values and has a record to prove it.”

A day after Gray was noncommittal about supporting his party’s mayoral nominee, all eyes were on him as he entered Matthews Memorial Baptist Church.

“We’ll see how things unfold. We’ll see how things unfold,” Gray told reporters. “At this stage, right now, we’re talking about bringing the whole party together. I think that’s the first stage in this process.”

Bowser said she was no longer waiting for a call from Gray. “You know, it’s tough to lose, and when the mayor is ready to talk, we’re going to be ready to listen.”

When Gray, who had to leave the event early, delivered 10 minutes of remarks, he did not acknowledge Bowser by name.

Instead, Gray used his remarks to lambaste a quirk of District government — that two of the council’s five at-large seats are reserved for members of non-majority parties (i.e., not Democrats). The set-aside, Gray said, made the council a “training ground” for the likes of Catania to launch citywide runs against Democrats.

“It is time to fight, Democrats,” Gray said, referring to Bowser only once, via a pronoun.

After he concluded his remarks, rather than stepping down and greeting Bowser, who was seated in front of the podium, Gray exited to the side of the stage and made a beeline for the rear entrance. There he was met by reporters. WRC-TV’s Mark Segraves asked Gray, “Why did you not shake Muriel Bowser’s hand at the Unity Breakfast?”

“It was not intentional, Mark,” the mayor said. “Don’t make a story out of this, because there is none. . . . Don’t make a story out of this. You will, because I’ve seen you do it before.”

A Washington Post reporter pointed out to Gray that he had not mentioned Bowser by name. “I’m going to go back and do that,” he said. “I’m going to go back and do that.”

While D.C. Democratic State Committee Chairman Anita D. Bonds was addressing the crowd, Gray returned to the center of the room, embraced Bowser and shared a few words out of earshot before leaving.

The crowd cheered and applauded, and Bonds interrupted her remarks.

“There we go! Muriel Bowser! Vincent Gray!” she said. “I don’t need to say anything else.”

Bowser, asked whether Gray had expressly offered his support, said: “He said, ‘Congratulations,’ basically. It was hard to follow what he was saying.”

Minutes later, Bowser asked the crowd to join her in “acknowledging” Gray. Talking to reporters, she added: “What the residents of the District of Columbia expect is that leaders will work together on a smooth transition.”