Mitt Romney has improved his chances of winning Michigan while he maintains a commanding lead in Arizona. Both primaries are scheduled for Tuesday.

Nate Silver:

A new Rasmussen Reports poll of Michigan gives Mr. Romney a six-point lead there, 40 percent to 34 percent. The poll, conducted after Wednesday night's debate, represents a reversal from Rasmussen's previous survey of the state, which had Mr. Santorum up by four points instead.

Mr. Romney also holds the lead in a second poll, from Mitchell Research and Rosetta Stone, which like the Rasmussen survey was conducted on Thursday after the debate. There is less in the way of momentum for Mr. Romney in this survey - he held a two-point lead in a poll conducted by the same firm earlier this week and has a three-point lead now - but it gives him an advantage nevertheless.

The FiveThirtyEight forecast model now projects a win for Mr. Romney by about four points in Michigan, roughly bisecting the Rasmussen Reports and Mitchell Research polls. Although that is inherently a fairly small margin, it is more meaningful given that there are just four full days of campaigning until Michigan votes; the model makes Mr. Romney about a 2:1 favorite in the state.

It's anybody's guess what Michigan voters will think of Romney's blunder in scheduling a speech at Ford Field and only 1,000 people showing up. Is it just inside politics to most voters or will the image of an empty stadium remind people of Romney's unpopularity?

Santorum's Super Pac is pouring money into the state so it's not too late for a turnaround. I am not as confident as Silver that Romney will win in Michigan.To win, Santorum will have to do very well in 6 rural counties that will supply the bulk of his votes. With Gingrich polling in single digits, it is possible that Santorum can build up a large lead in those counties and hang on to narrowly defeat Romney.

In any case, it should be a long night.

Arizona is a different story. Silver projects a 94% chance of a Romney victory. Recent polls have shown the candidate with a double digit lead and Santorum is not making much of an effort in the state.