The Michigan State Senate just passed a bill establishing a joint presidential primary on Jan. 15.

All the chambers' Republicans voted yes; all the chambers' Democrats voted no.

Many Democrats objected on technical grounds.

The bill will now have to be reconciled with a version passed by the state house of representatives.

Gov. Jennifer Granholm is eager to sign the bill.

More analysis, later.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.