His smallest drop-off is in North Carolina, which he carried only 50 to 49 percent but where voters seem sharply polarized. It's a particular target for Obama, who chose Charlotte as the site of the Democratic National Convention.
Romney is running even in recent Florida polls and less than 5 points behind in Iowa, New Hampshire, North Carolina, Ohio and Virginia -- within striking distance. If he wins them all plus safe Republican states, he'll be elected.
That's without Colorado, Michigan, Nevada, New Mexico, Pennsylvania and Wisconsin, with 66 electoral votes in all, which could conceivably be within Romney's reach.
Democrats hope to expand the field to Arizona, with 11 electoral votes, and Republicans hope to expand it to New Jersey, with 14. Those hopes may look dim now, but at this point in 2008 few expected Obama to carry North Carolina or Indiana.
The bottom line is that at this point Obama doesn't have an Electoral College lock. Neither does Romney. The numbers tell us that this election is up for grabs.
The Obama campaign has prepared for a long, hard slog through the target states. The Romney campaign is getting prepared for the same.
It's what the political press expects and has tried to prepare for. We feel we have a pretty good sense of the relevant terrain.
But in politics there are sometimes surprises, unanticipated changes, developments that seem obvious in retrospect but were wholly unexpected before they happened. The long, hard slog is the likeliest scenario for 2012. But in a future column I will sketch some alternative possibilities.