As soon as the polls closed in Arizona tonight, the networks declared Mitt Romney the winner of the state’s Republican primary. The state’s winner-take-all format will ensure that all of Arizona’s 29 delegates go to Romney, which makes it a not inconsiderable prize. Romney’s decisive advantage there makes it an impressive win but unfortunately for him, his Arizona triumph won’t mean much if he can’t hold onto the slim lead he currently holds in Michigan.
Michigan remains the true test tonight and a Santorum win there will be a devastating blow to the frontrunner. Santorum’s camp will, not without some justice, proclaim even a close loss there as a moral victory for their candidate. But if Romney escapes his native state with a victory of any kind, it will be a lost opportunity for Santorum. An upset in Michigan is his best chance to knock off his rival.