Your amazement regarding the Presidents ongoing buoyancy in the polls is well placed, especially in light of May's dispiriting jobs numbers. But my guess is that the encouraging poll numbers represent an illusion for Democrats (including myself) and the president. I googled the Reagan Carter numbers for comparison and they tell a very clear story. Until a week before the election, Carter led most surveys, yet he was never going to win (unless he could portray Reagan as a dangerous lunatic, and that was never going to happen). The number that really mattered was Carter's historically dismal approval rating; 31% on election day and not much better for months beforehand. At 48%, Obama is not quite out of the game but he is in a great deal of trouble.
While I, along with many economists, do not fault the President for the tepid recovery from the Great Recession of 2008, he and the Dems will have to play the hand they're dealt. And the Europeans incapacity for avoiding disaster can only damage his chances further (not to mention my retirement portfolio).
So we are going to have a nasty election in which the Repubs are going to to what they do best, which is to belittle and dirty up the other guy. On the other side, a sharp elbowed Chicago poll is going to do everything he can to disqualify the challenger, because that may be his only hope of holding onto the White House.