Mark your calendar. A respected numbers-crunching blog predicts that Utah will swing in favor of same-sex marriages by 2013.

It's apparently gets harder every year to pass gay-marriage bans. FiveThirtyEight built a statistical model based on the religious intensity of voters, the percentage of white evangelicals in residence and some other stuff to predict when each state's citizens would swing around to vote against same-sex marriage bans.

Here's the predictions for western states:

2009 (now)
Nevada
Washington
Alaska
Oregon

2010
California
Hawaii
Montana
Colorado

2011
Wyoming
Idaho
Arizona

2013
Utah

2014
New Mexico

For complete results and a detailed explanation of the model, go here. By the way, the model is supported by Vermont's veto-override legalization of gay marriage.