Obama's pre-presidential political career is a study in good luck. When he ran for the State Senate his primary opponent was caught up in a sex scandal. He lost a race for US congress. Why is this good luck? A. It got him a lot of positive PR. B. Going to the House might well have made him a "back-bencher" for a long time. (The same thing happened, by the way, to the prior Democratic president, Bill Clinton, who lost a House race 2 yrs before being elected Governor.) Then the Ryan brouhaha. Then, as he seeks the Presidency, the economy implodes under the other party's watch.
This may explain why his presidency was so rocky. He'd used up enough good luck for two careers. But then, on the other hand, he was reelected with economic numbers that might have spelled a certain loss in other times, so go figure.