After a long stretch of inactivity in terms of actually voting, the Republican nomination contest fires back up tonight with Michigan and Arizona going to the polls.  Most of us won’t be able to turn anywhere tonight without seeing coverage of what happens, but here are five things we’ll be watching here at WPA that may not get a lot of reporting in the big-picture coverage.

1)      Does Romney continue to under-perform?

One of the most interesting stories to me so far this year is that Romney just seems to always fall a little short of expectations.  Whether it was under-performing his polling advantage in New Hampshire or a late collapse and eventual shellacking in South Carolina, Romney only seems to have met expectations in Florida.

Now in Michigan, even a Romney win runs the real risk of under-performing his 2008 primary vote.  And this in a state where he has both a home-field advantage and, like Florida, where he has made full use of his ability to outspend his opponents.

2)      Does the delegate allocation follow the popular vote and how does it get reported?

Michigan, like a number of primary states, allocates delegates to the winner of each Congressional District rather than winner-take-all (two delegates are awarded to the statewide winner).  Nate Silver at the New York Times had a good review of all of the different ways in which delegates are awarded this year, for those of you who enjoy getting down in the nuts and bolts of the process.

What this means is that it’s possible for one candidate to “win” the popular vote while another takes more delegates.  This is more likely than it might appear as Romney has a real chance to run up big wins in the affluent Detroit suburbs while Santorum may well win more districts throughout the state.  If that scenario comes to pass, it will be interesting to see how the primary is reported—could we be in another situation where Romney “wins” tonight and then Santorum “wins” tomorrow on further reflection?

3)      Does Romney win middle-income (or lower) voters?

One of the big drivers of this primary cycle has been Mitt Romney’s difficulty in winning over the middle and lower-middle class voters who have flocked to the GOP in recent years.  Michigan will be his best chance to show that he can win these voters in large numbers because he’ll have both a home state and spending advantage to bolster his numbers.

If Romney still loses these voters badly, that can’t bode well for his chances on Super Tuesday in either the Midwest or the South.

4)      How much airplay does Arizona get?

In terms of delegate count, tonight will be a good night for Mitt Romney.  Even a loss in Michigan is likely to result in a split of the delegates while Arizona, which he seems almost certain to win, will award its delegates winner-take-all.

But the outcome in Arizona has never been in much doubt.  If a big Romney win there gets widely reported, it may help insulate him against a poor outcome in Michigan.  But if the story is mostly about a loss in Michigan, the momentum effects headed toward Super Tuesday could be problematic for him.

5)      How big of a role does Newt play?

Newt Gingrich is not going to be the Republican nominee.  But he has apparently decided to hold on through Super Tuesday for reasons of his own.  He’s currently polling around ten percent in Michigan.  Most of those votes would likely go to Santorum if Newt were absent from the race.

If the outcome in Michigan is a close Santorum loss, Newt’s decision to stay in and play “spoiler” may be the biggest story of the night.  How it gets told and how that impacts the run-up to Super Tuesday would be fascinating—but will it get covered at all?