The second and broader challenge the president faces is restoring his credibility, not only on health care but also on his overall leadership. It could take years for the public to reach a full judgment on the Affordable Care Act. With talk already turning to the contest to succeed him, the president knows he has only a limited amount of time in which to get back on top of things.

Obama is dismissive of the crisis-an-hour mentality that often grips the political chattering class. He has endured low moments throughout his political career and has found a way to ride them out. He is famously patient. But he is now in a hole of his own making.

He decided to risk enactment of comprehensive health-care reform along strictly partisan lines because he concluded there might not be another chance in his presidency to do what one after another of his predecessors had failed to do. He may have been correct that this was his best opportunity, but it was a big bet with long-term consequences. At the same time, he made claims about the new law, selling-points designed as part of a political sales job, that have been called into question, compounding his problems.

The latest report cards on the president’s performance chart the decline in his standing in the year since he was reelected. The Pew Research Center, in a poll released late last week, pegs his approval rating at 41 percent. That is 14 points lower than it was at the end of last year…

Rhodes Cook, an independent analyst of elections, put together a chart on the eve of the 2010 midterm elections that compared presidential approval with the success of the president’s party in midterm campaigns. For Democrats a year away from 2014, the findings should be sobering. Looking at midterm elections dating back to John F. Kennedy’s presidency, no president with an approval rating below 50 percent has seen his party gain seats.