Santorum Delivers a GOP Stunner Former Senator Wins in Minnesota, Missouri; Romney Campaign Plays Down Nonbinding Contests By NEIL KING JR. And DANNY YADRON DENVER—Rick Santorum jolted the Republican presidential race Tuesday by winning nominating contests in Missouri and Minnesota, puncturing Mitt Romney's claim to be the unstoppable front-runner. Mr. Santorum, a former Pennsylvania senator, was running neck and neck with Mr. Romney in preliminary returns from Colorado, a state Mr. Romney won by a wide margin in 2008. With about 70% of the Colorado vote counted, Mr. Santorum had 38%, to 36% for Mr. Romney. Four years ago, Mr....
