For those of you who don't know (and unless you're a true-blue political nerd or have read the FAQ, you probably don't), this site is named after the number of electors in the Electoral College, a number which, since the passage of the 23rd Amendment in 1961, has been fixed at 538, equal to the 100 members of the United States Senate, plus the 435 members of the United States House, plus three more for the District of Columbia. But this number is not fixed by the Constitution. If the number of persons in the Congress changes, so will the number of votes in the Electoral College.
And it looks like the number of votes in the Congress will in fact be changing. On Tuesday, the Senate achieved cloture (broke a filibuster) on S.160, the District of Columbia House Voting Rights Act of 2009, which would (1) permanently expand the size of the House from 435 to 437 members and (2) give one of these additional seats to the District of Columbia. This measure is quite likely to formally pass the Senate soon, be followed up with a vote in the House, and be signed by the President. Unless it is struck down on a Constitutional basis (and it will certainly be challenged), it will become the law.
So in all likelihood, we'll have two new Congresspersons beginning with the meeting of the 112th Congress in 2011. This will in turn affect the Electoral College. The reason the number of electors will increase from 538 to 539 (rather than 540) is because, under the 23rd Amendment, D.C. is already essentially given credit for having a having a vote in the House and so adding an additional voting member in the House is redundant. This has the convenient feature of placing an odd number of total electors in the Electoral College, which means that an Electoral College tie will be impossible in a two-candidate race.
If you've been following the D.C. Voting Rights Act, you might have sometimes heard it said that the Congress was trading a (presumably Democratic) vote in D.C. for a (presumably Republican) vote in Utah. This is not technically true. All the measure does is apportion one additional vote in the House between the 50 states based on the existing formula. It just so happened that, under that formula, Utah got the the short end of the stick and was the next state in line for an additional Congressman anyway. For the 112th Congress, which will be elected in 2010 and whose membership is still determined by the 2000 Census, Utah will gain an additional elected member. But there are no guarantees about which state will benefit in 2012 and beyond ... it could be that the extra seat helps a Republican state like Utah to gain an additional member (in fact, Utah is nearly certain to gain a voting member anyway because of its high population growth), or it could be that the extra vote saves a deep blue state like New York from losing one. So this is a pretty good trade-off for the Democrats: they'd essentially gain a vote in the House permanently (unless aliens take over and D.C. turns Republican) in exchange for giving Utah an extra vote for just two years.
As for this website, we will not be changing our name. FiveThirtyNine.com was already purchased by an forward-thinking German entrepreneur last summer, and besides that, we've built up quite a following for ourselves under this brand name.
But if the Supreme Court finds some excuse to strike this down ... well, I wouldn't entirely mind.