One day after he lost his bid for an at-large seat on the D.C. Council, A.J. Cooper said he’s already making plans to compete in the upcoming special election to fill the citywide council seat left vacant by Phil Mendelson’s election as chairman.

Cooper, 32, tied for fifth place in Tuesday’s election in which challenger David Grosso defeated incumbent Michael A. Brown (I) for one of two at-large seats on the D.C. Council.

AJ Cooper (r) talks to an attendee. (Macy L. Freeman/The Washington Post)

Cooper will likely be entering a crowded field for the Mendelson’s at-large seat. Ward 1 school board member Patrick Mara, Ward 1 community activist Bryan Weaver, and D.C. Democratic Committee Chairwoman Anita Bonds have all been mentioned as potential candidates.

Brown also could choose to enter the race to rejoin the council. But in an interview early Wednesday morning after he was defeated by Grosso, Brown said it was premature to speculate  on his political future.

The D.C. Board of Elections not yet set the date of the special election, but officials have said it will likely be this spring.

“I think I can win and think the voters of DC need to be able to get another new council member who represents the residents of the city,” said Cooper, policy director of the D.C. Campaign to Prevent Teen Pregnancy. “I think a lot of people in this city voted for me and I think a lot more are becoming aware of who I am as a candidate and they would like to vote for me.”

During candidates forums and debates, Cooper emerged as a relentless critic of Brown’s series of personal and financial missteps. Cooper also appeared to mobilize a coalition of younger residents eager to have more a voice in District affairs.

 He established some ties with progressive groups, winning an endorsement from the D.C.’s Tenants Advocacy Coalition.  D.C. Council member Tommy Wells (D-Ward 6) also indirectly announced his support for Cooper a few weeks before the election.

Cooper comes from a prominent local family. His father, Algernon Johnson Cooper, was elected mayor of Pritchard, Ala., in 1972, becoming the first black mayor of a majority-white city in the state.

While in high school and college, A.J. Cooper was the host of Black Entertainment Television’s “Teen Summit” program.

He is from a family of strong Democrats, but did not register with a party when he turned 18 in what he says was a rebellious act to prove his independence. His aunt is Peggy Cooper Cafritz, a philanthropist and former school board member.

Despite his family network in the city, Cooper ran a low-budget campaign against Brown and Grosso. In past interviews, he said his family wanted him to prove his own abilities before they become extensively involved in his political effort.

In the upcoming special election, Cooper said he will have more time both to raise money and woo potential voters.

“We are already on the minds of people, so I think we’ve got an advantage,” Cooper said.