The Gallup state-by-state average approval numbers for 2011 released this week don't necessarily predict where President Obama will finish on Election Day, but they do measure the hill he must climb to win re-election.
The most important number in presidential elections, of course, is 270 - the number of Electoral College votes it takes to win. The best way to examine the Gallup numbers is to measure them against that yardstick.
In 2010, if you sorted down from Obama's highest approval rating to his lowest, he could reach 270 Electoral College votes by carrying the 22 states plus the District of Columbia where his approval rating stood at 46.9 percent or more. Since one of the states above that line was Mississippi, a state Obama has almost no chance of carrying in practice, a more realistic scenario was that to reach an Electoral College majority he would have to carry those 21 states plus Virginia, where his approval rating stood at 46.6 percent.