Twitter is almost as popular in Washington as lobbyist-funded junkets. Elected officials use Twitter as a channel to talk directly with the people, communicating from fact-finding missions to Baghdad and during the State of the Union Address. Sen. John McCain even did a Twitter interview. But who are the top political Twitterers? I've compiled a quick-and-dirty list here; if I'm leaving anyone out, please let me know.
Jimmy Stewart's passionate filibuster in Mr. Smith Goes To Washington would probably have been less effective if he'd tweeted it.

Barack Obama, 574,576 followers. He was the most popular account on Twitter for months -- even though he only updated three times since Election Day, but recently he was bumped by four other Twitterers -- including Britney Spears and Ashton Kutcher. (Oh, come on!)

Al Gore, 466,048 followers -- and he doesn't even hold office anymore.

NPR Politics, 404,580 followers.

Downing Street, 346,116 followers. It's kind of like the White House, only it's in London.

George Stephanopoulis, 286,885 followers, political correspondent, ABC News, still has great hair.

John McCain, 341,080 followers.

World Economic Forum, Davos, 281,867 followers.

Ana Marie Cox, 269,657 followers, National Correspondent for Air America Radio, former Wonkette.

John Dickerson, 258,780 followers. Political correspondent, Slate.

Rachel Maddow, 244,780 followers, MSNBC.

Gavin Newsom, 167,271 followers, San Francisco Mayor.

Want more? SourceWatch has a lost of 69 members of Congress who Twitter.