Just as the political air is filled with talk of the inevitability of Barack Obama's re-election -- we are told that the kids at his Chicago headquarters are brimming with confidence -- in come some poll numbers showing him behind.

Last week I wrote about the standings in the presidential race and said it looked like a long, hard slog through about a dozen clearly identified target states, much like the contests in 2000 and 2004. Call it the 2000/2004 long, hard slog scenario.

One approach for Mitt Romney would be what opponents might call a double-vanilla ticket, with another white male as vice presidential nominee. Four possibilities come to mind.

Rick Santorum won big victories in three small contests in the Republican presidential race last Tuesday. In doing so he reshaped the oft-reshaped nomination battle once again. But he has not installed himself as the favorite, and neither he nor Mitt Romney has established himself as the candidate who can do best in the general election.

Romney was the big, big winner in delegates, but that doesn't mean that he'll be handed the nomination.

At last, after pundits, pollsters and politicians have filled the media for months with their wisdom, tomorrow in Iowa, actual American voters begin actual voting in an actual caucus. Be prepared to be surprised.

Mitt Romney's impressive victory Tuesday makes it very likely that we will look back on the Florida primary as the contest that determined the 2012 Republican nomination. To be sure, the campaign fight will go on, and Romney is by no means assured of a sweep of the relatively few February contests.

Mitt Romney is the most improbable of presidential candidates: a weak juggernaut. He is poised to sweep every primary contest — a first for a non-incumbent. And yet, in Republican ranks there's an abiding sense that he should be beatable — and beaten.