The Pew Research Center's national polls tend to generate more attention than most because their recent track record is quite good. Pew's final 2008 poll, for example, showed Barack Obama leading by 6 points nationwide, and he won by 7 points. Pew's final 2004 polled George W. Bush leading by 3, and he won by 2.5.
With that in mind, it's worth noting that Pew's final 2012 poll shows the president ahead by three, 48% to 45%. I made chart showing to highlight the larger trend.
You'll notice, of course, that immediately after Obama's first debate with Mitt Romney, the Democrat's standing saw a sharp decline, to the point that the Republican inched ahead a month ago. In the ensuing weeks, however, the president's support recovered (though it remains short of where it was in September).
There was, however, one other detail that stood out for me: among likely voters 39% support Obama "strongly," as compared to 33% who say the same about his challenger. Why is that significant? Because in the post-Watergate era, the only other candidates to have 39% "strong" support going into Election Day were Reagan in 1984 and Bush in 2004.
Both of them won.
One other thing: when Pew showed Obama's support collapsing after the Denver debate, the gender gap vanished and the president was tied with Romney among women. Now, however, the gap has returned, and Obama leads Romney among women by 13 points (53% to 40%), while men prefer Romney by 8 points (50% to 42%).