Polls show Mitt Romney and Rick Santorum still neck-and-neck in Michigan, but one Santorum staffer says the former Pennsylvania senator has “already won” there.

“We have already won,” Santorum adviser John Brabender said on CNN. “No matter what the results are, we’ve won. This is Romney’s home state.” …

Both Santorum’s campaign and Romney’s campaign have been spending a significant amount of resources in Michigan. Brabender argued that the more money the Romney campaign spends there, the less it will have for primary states on Super Tuesday.

“The Romney campaign is spending a fortune they never expected to spend in Michigan, and every dollar they spend in Michigan is a dollar they don’t have on Super Tuesday,” he said.

With these remarks, Brabender simultaneously reminded voters that it was and is an accomplishment for Santorum to be competitive in Michigan and tamped down expectations of an actual Santorum victory in the Mitten State.

Polls don’t necessarily indicate that Santorum needs to mitigate expectations, though. While a new survey from Public Policy Polling shows Romney with a slight edge over Santorum, other polls favor the former Pennsylvania senator. A new poll from the American Research Group, for example, gives Santorum the advantage — albeit a very small one. According to ARG, Santorum leads Romney 36 to 35.

Brabender’s argument that Romney’s Super Tuesday showing will be less impressive in proportion to the amount of time and money he had to spend in Michigan makes sense, too — and, indeed, polls have already shown Santorum with sizable leads in at least a couple Super Tuesday states. A new poll from Quinnipiac University, for example, shows him with a 7-point lead in Ohio.

Then again, the false-self-esteem-boosting “we’re all winners” line doesn’t apply to the presidential primary process. As Mitt Romney spokesperson Andrea Saul put it, “You don’t win by losing,” and, if Santorum does lose Michigan, he might also lose some of the momentum he’s built in Super Tuesday states. Much of the excitement about Rick Santorum has stemmed from the mounting evidence that he can successfully challenge Mitt Romney all the way to the nomination. Losing Michigan won’t add to that evidence.

Tomorrow matters. Who wins matters — no matter what campaign advisers on either side say.