The results from Iowa with over 90 percent of precincts reporting show Rick Santorum and Mitt Romney in a dead heat with 25 percent of the vote each, with Ron Paul third with 21 percent of the vote.
This is not a surprise. The Republican party has three factions: religious conservatives, economic conservatives, and libertarians. Each faction is represented by one of these three candidates (in the order listed above). What shifted over the past few months was which candidate would represent the religious conservatives. It turned out to be Santorum, rather than Bachmann or Perry.
The Iowa caucus is not supposed to determine the nominee. It is primarily the media circus surrounding it that makes it appear to be more consequential than it is. Ezra Klein had a good post on this a day ago. Iowa matters beyond the delegates it awards because it provides information that is useful to others who are deciding which candidate to support -- and because an abysmal showing might convince a marginal candidate to drop out of the race. That might be Bachmann here. Huntsman ignored Iowa to focus on New Hampshire, and Perry might as well hold on until South Carolina.