The immigration debate has rattled many and may tip them toward the Democrats. But which one?
Romney's Michigan win deepened GOP uncertainty before crucial upcoming contests.
Now, the Republican presidential nomination battle shifts from the typical tack of achieving inevitability to one where candidates work to amass the most delegates.
Indicators like high oil prices and the slumping stock market have voters concerned.
The state's economic woes are the central focus for Romney, McCain, and Huckabee before Tuesday's primary.
On the Democratic side, a potentially historic clash lies ahead. For the GOP, Michigan is the next test.
Results in the Granite State mean frontrunners in both parties will continue to duke it out for the nomination.