Less than a week before Tuesday’s crucial Republican presidential primary in Michigan, a new NBC News/Marist poll shows Mitt Romney and Rick Santorum locked in a statistical tie, while a separate NBC/Marist survey shows Romney comfortably leading in Arizona, which holds its primary the same day.

In Michigan – which has turned into a make-or-break contest for Romney – the former Massachusetts governor gets the support of 37 percent of likely GOP primary voters, including those who are leaning toward a particular candidate.

NBC-Marist poll results: Michigan | Arizona