That does almost nothing to address voters' concerns, which remain a potent factor in the campaign. The bottom line is, there's a reason Republicans keep pushing so hard against Obamacare: So far, it's working.

The Obama damage is two-fold. First, his success relied on a coalition that likely will not survive, or at least survive at full strength, without Obama himself on the ticket. Secondly, Obama drove a significant portion of white voters away from the Democratic Party.

If one cannot imagine Obama saying such a thing — well, he didn't.

In the end, no single group will mean defeat for the Democrat and victory for the Republican in 2016. But President Obama's troubling legacy - a weakened coalition and growing ranks of alienated white voters - could mean a serious post-presidential hangover for Democrats.

As Democratic losses mounted in Senate races across the country on election night, some liberal commentators clung to the idea that dissatisfied voters were sending a generally anti-incumbent message, and not specifically repudiating Democratic officeholders. But the facts of the election just don't support that story.

Now that the 2014 elections are over and national politics is all about 2016, Democrats have good reason to worry that, for all his success at the polls, President Obama will leave his party with a toxic legacy.

Perhaps the most striking thing about the 2015 State of the Union address was not the president at the podium but the audience in the seats. The joint session of Congress listening to President Obama Tuesday night included 83 fewer Democrats than the group that heard Obama's first address in 2009 - 69 fewer Democrats in the House and 14 fewer in the Senate. The scene in the House Chamber was a graphic reminder of the terrible toll the Obama years have taken on Capitol Hill Democrats.