The field of Democrats angling to replace retiring Rep. James P. Moran keeps growing as two more candidates are jumping into the Northern Virginia contest.

Mark Levine, a liberal talk-­radio host whose interest in the seat was already known, has made his entry into the race official. And Derek Hyra, a Virginia Tech professor active in Alexandria city government, is jumping into the battle Tuesday.

The contest has become a magnet for Democrats because the 8th District — which includes Alexandria, Arlington, Falls Church and part of Fairfax County — is solidly blue. It gave President Obama 67 percent of the vote in 2012.

The winner of the June Democratic primary is very likely to win the seat in November and could hold it for many years to come.

“This campaign is not going to be won on who has the most money and who has the greatest name recognition,” Hyra said. “It’s going to be who knocks on the most doors and . . . who inspires people.”

Hyra, 40, is an associate professor of urban affairs and planning at Virginia Tech’s Alexandria campus. He previously worked at the U.S.Treasury and Housing and Urban Development departments. He chairs the Alexandria Redevelopment and Housing Authority and is a member of the Alexandria Planning Commission.

Levine, 47, is the host of a syndicated talk show, “The Inside Scoop,” and has hosted or appeared on several other programs. He previously served as a top attorney for then-Rep. Barney Frank (D-Mass.) and has been a teacher and a U.S. Justice Department lawyer.

Levine said he would distinguish himself from the other candidates by being “an aggressive progressive who doesn’t just cast one out of 435 votes.” With his media savvy, Levine said, “we can go over the heads of the Republican Party to the American people.”

In addition to Hyra and Levine, the Democratic field includes state Sen. Adam P. Ebbin (Alexandria) and state Dels. Charniele L. Herring (Alexandria), Patrick A. Hope (Arlington), Alfonso H. Lopez (Arlington) and Mark D. Sickles (Fairfax). Former lieutenant governor Donald S. Beyer, ex-Northern Virginia Urban League head Lavern Chatman, Alexandria Mayor William D. Euille and 2012 candidate Bruce Shuttleworth are also in the race.

Former congressional aide Micah Edmond is running for the Republican nomination.