Former Virginia lieutenant governor Don Beyer is poised to enter the race to succeed retiring U.S. Rep. James Moran, a move that will inject more drama — and money — into a closely watched contest.

Beyer (D), the co-owner of several successful car dealerships, served as lieutenant governor for two terms before losing the 1997 race for governor. From 2009 to 2013, he served as U.S. ambassador to Switzerland and Liechtenstein, and now he is plotting his next step: Congress.

“Yes, my plans are coming together,” Beyer said in an e-mail Sunday. “I do plan to file the appropriate paperwork [Monday] or Tuesday with the Federal Election Commission and the Virginia State Board of Elections. Next step: 1,000 valid 8th District signatures!”

Beyer will join a crowded Democratic field for a seat in that serves Arlington, Alexandria, Falls Church and part of Fairfax County.

Del. Mark C. Sickles (D-Fairfax) said Monday he was also entering the race. He unveiled a handful of endorsements, including that of Sharon Bulova (D), chairman of the Fairfax County Board of Supervisors.

Del. Charniele Herring (Alexandria) announced her campaign last week, meaning she will step down in March as chair of the Democratic Party of Virginia. Del. Patrick Hope (Arlington) and 2012 candidate Bruce Shuttleworth have also launched their bids. And state Sen. Adam P. Ebbin (Alexandria), Del. Alfonso H. Lopez (Arlington) and Alexandria Mayor William D. Euille are expected to run as well.

In a heavily Democratic district, several of those candidates could appeal to liberal interest groups. Herring, probably the only woman, has been encouraged by Emily’s List.

But Beyer brings a different advantage: wealth. He declined to address the question of how much of his own money he might spend on the campaign. But if Beyer is willing to spend six or seven figures out of his own pocket, it could transform the race.

On the Republican side, former congressional aide Micah Edmond has entered the contest.