The results are nonbinding, and thus do not have any direct bearing on how Iowa’s national convention delegates are apportioned. Sometimes the vote taken at the Iowa caucuses is called a “preference poll,” because all it does is indicate voter preferences on that day. Nevertheless, the result will play a critical role in the 2012 GOP nomination process, most likely in winnowing the field as lower finishers find they don't have the resources to continue.
The caucus meetings also serve as the forum for selection of delegates to later county and state conventions, and the eventual selection of delegates to the Republican National Convention. So they are a party-building tool. In all, Iowa sends 28 delegates to the national convention in August. Twelve are elected from the state’s four congressional districts. The other 16 come out of the state convention in June. To win the GOP nomination, a candidate needs the support of 1,144 delegates.