GOP contests under way in Minnesota, Missouri, Colorado

Updated at 9:05 p.m. ET

The doors have closed at Missouri polling precincts and caucus locations in Minnesota and Colorado, where voters will weigh in tonight on the Republican presidential nomination.

Officially, a total of zero delegates will be awarded after Tuesday's contests: The Colorado and Minnesota caucuses are the first step in a long process to assign delegates, and the Missouri primary is considered a "beauty contest," since delegates will be awarded after the state's March 17 caucuses. Still, the nominating contests could give some indication of which candidates have lasting momentum.

Former Massachusetts Gov. Mitt Romney could have the advantage. Romney, who handily won the Florida primary and Nevada caucuses last week, easily won both Colorado and Minnesota in the 2008 Republican presidential primaries. In Minnesota, Romney should also benefit from the fact that independents are permitted to participate in the caucuses. Romney also has the frontrunner status going into Tuesday, after winning three of the first five contests.

However, the former governor sought to tamp down expectations Tuesday, signaling his GOP rivals, particularly former Sen. Rick Santorum, could have a strong night. New polls from Public Policy Polling, a Democratic polling firm, show Santorum with a strong lead in Minnesota and Missouri. Former House Speaker Newt Gingrich failed to get on the ballot in Missouri.

PPP polling indicates Romney should do well in Colorado, where he has campaigned for several days. However, either Santorum or Gingrich could perform well, since the caucus is open only to Republicans, and Colorado has a sizable number of evangelical voters.

Romney currently has 94 delegates allotted to him in the latest CBS News estimate of both pledged and unpledged delegates. Gingrich has 30, Santorum has 17 and Rep. Ron Paul of Texas has eight.

Colorado election results
Minnesota election results
Missouri election results