A National League team is coming to the District. Let’s name 'em.
I say bring back the Senators moniker.
The Monuments.
The Monicas. After a short bit of headline-grabbing news, everyone will realize that they suck, and soon, nobody will care anymore.
The Washington Bullets.
The Belt-A-Ways.
The Beltway Snipers.
The Washington George.
I say name em for what DC is most famous for:
Bureaucratic Red Tape!
or
Deficit Spending
or
Professional Politicians
or
I like plnnr’s suggestion of bringing back Senators.
May as well accept the inevitable and call them the Portland Wolves now. I give them 15 years in DC.
Salut Youppi! And good riddance!
Why not just call them what they should have named in the first place: The Norfolk Expos!!!
But I suppose it’s too much to ask the DC area baseball fans to drive 30 miles to see a MLB game.
Have they officially decided not to keep the name Expos? I haven’t yet found one article that has alluded to the intent to change the name.
Teams move all the time and keep their original monikers. Just ask the Memphis Grizzlies, New Orleans Hornets, Arizona Cardinals, and St. Louis Rams.
The name “Expos” has taken on a very negative connotation with the shoddy management of the club since the cruel canceled season of 1994. I think it would be best for the franchise to distance itself from its past. I think a better historical precedent was the change from the St. Louis Browns to the Baltimore Orioles in 1954. Orioles was the historical name of the 19th century Balitimore baseball teams and the Browns were the Expos of those days, a desparately broken down franchise that needed a complete fresh start.
Since few people likely have fond memories of the old Senators, I suggest a brand new name…actually “Monuments” doesn’t sound half bad. 
However, if they don’t put up a statue of Walter Johnson outside their future stadium, they deserve to inherit all the bad karma that is Washington baseball.
Don’t forget about the Tennessee Oilers, the Washington Senators (twice), the Cleveland Browns, the Seattle Pilots, the Buffalo Braves, the Minnesota North Stars, the Quebec Nordiques and the St. Louis Browns (and the Washington Bullets, one of many teams who changed names without changing cities), just off the top of my head.
Why should they do that? It’d make about as much sense as the Mets putting up a statue for Pee Wee Reese or the Red Sox putting one up for Eddie Mathews, or the Indians putting up a statue to Cy Young, or the Phillies putting up statues honoring Ty Cobb or Chief Bender, or the Royals honoring Roger Maris. What baseball connection (not geographic, baseball) is there between Johnson’s old team and the soon-to-be-formerly Montreal team?
They’ll be horrible because they have about as much talent as the Richmond Braves - had they been allowed to keep Vlad Guerrero, they’d be looking a lot better, but as things stand it’s like the Diamondbacks moved to DC except without Randy Johnson.
I like the “Washington Federals”. It was the name of one of the former USFL teams. The team was lousy, but it had a cool logo and uniforms, IMHO.
I also like “Washington Generals”, but I wonder if the Harlem Globetrotters owns that trademark.
Other possibilities – Admirals, Colonels, Capitols (probable confusion w/NHL Capitals?), Barons (former Cleveland NHL team), Statesmen
Ok, I know why Montreal named the team Expos and all, but I always pictured a bunch of dirty old men in overcoats. Hmmm… come to think of it… hell, that would be suited to DC. 
Actually, they don’t. The trademark - for basketball only and no longer used by the way - is owned by Red Koltz Sports Enterprises.