Fox News reports:
Mitt Romney has won the Michigan Republican presidential primary, Fox News projects.
The New York Times adds:
Mr. Romney has narrowly won the Republican presidential primary in Michigan, deflecting a powerful challenge from Mr. Santorum and bolstering his hopes of becoming the Republican nominee.
Only weeks ago, Mr. Romney had viewed his home state of Michigan as a firewall against his rivals, an important battleground state where his background and his message would carry the day.
That changed dramatically in the wake of victories by Mr. Santorum in Colorado, Missouri and Minnesota this month. Within days, Mr. Santorum surged to a double-digit lead in Michigan.
In the past two weeks, Mr. Romney battled back, aided by millions of dollars in negative campaign ads broadcast by the "super PAC" backing his campaign, and a stepped-up attack on Mr. Santorum's record.