Did Tuesday’s results matter? Nowhere near as much as the results from Iowa, New Hampshire, South Carolina, and Florida mattered. But primary campaigns rarely reach stasis; momentum shifts, ebbs, and flows, and the trio of contests yesterday offered a few hints that the storyline will change once again.

Rick Santorum is on the verge of overtaking Newt Gingrich as the anti-Romney alternative.

Santorum began this contest as the man of the hour, the little engine that could in a sweater-vest who challenged and beat the much-better-funded Mitt Romney . . . and yet he has, at the moment, an entire three delegates committed to him. (Iowa’s delegates to the national convention will formally be selected at a state convention on June 16.)

Santorum won no more than 17 percent in any of the subsequent contests, until last night, and he finished with a disappointing 10 percent in Nevada’s caucuses Saturday. Gingrich has declared, with increasing loudness and insistence, that the former Pennsylvania senator should leave the race to unite conservatives behind his candidacy.

Thirty-five days after the Iowa caucuses, Rick Santorum needed a win — even a purely symbolic win — to remind Republicans nationwide that he was still a serious contender. Tuesday night, he got it. Missouri was called for him first, shortly thereafter Minnesota followed, and in Colorado he looked likely to finish no worse than a close second. His two wins were landslides.

For conservatives hoping to unite behind one Romney rival, Missouri offered a tantalizing look at what the race would be like if Gingrich and Santorum were not splitting that segment of the GOP electorate.

Gingrich was not listed on the Missouri ballot; he and his campaign said that they did not bother to qualify for it because they deemed the nonbinding contest irrelevant. Cynics may notice the Gingrich campaign’s inability to qualify for the ballot in Virginia and wonder just how deliberate their approach to Missouri was.

In the reduced field, Santorum didn’t just win, he thrashed Romney. With 90 percent of precincts reporting, Santorum led in every Missouri county that was reporting results.

Rick Santorum adviser John Brabender told CNBC’s John Harwood: “Missouri tells me that in a clean one-on-one against Romney, we beat him.” Expect to hear a lot of this argument from Santorum and his supporters. You’ll also hear quite a few assertions that Santorum has won three contests to Gingrich’s one; the former speaker and his backers will furiously dispute that any of tonight’s results count as legitimate wins.

“We doubled him up in Missouri and Minnesota!” Santorum exulted in his victory speech last night. He added, “In Massachusetts, your votes were particularly loud tonight!”

Of course, it seems hard to imagine Gingrich voluntarily leaving the race; last night, he told Wolf Blitzer: “I’m certainly in it all the way to the convention.”

Santorum’s support surged dramatically in the final days before the Iowa caucuses, as polling indicated the former senator had a chance to win and would not be regarded as a “wasted vote.” Perhaps the largest obstacle to Santorum’s campaign is clearing that psychological threshold nationally; if so, last night and its consequent surge of funds and volunteers should go a long way.

The next binding, delegate-determining, real contests come February 28 in Michigan and Arizona. While both states will receive intense attention from the remaining campaigns, expect Gingrich and Santorum to go toe-to-toe in Arizona.

The RNC’s efforts to clean up the primary calendar seem only to have muddied things further.

In 2008, Iowa held its caucuses on January 3, a wildly early date. Previous primaries had been held no earlier than January 19 (2004, 1976), and the primary was held in February from 1984 through 1996. In response to the perception that the nomination process began way too early, and to prevent too many states from frontloading it, the RNC ruled that states that held their contests before March 6 would lose half their delegates. (Iowa managed to avoid losing delegates because its caucus was not officially binding; as noted above, the delegates will be picked at the state convention on June 16.)

Five states decided that an early calendar slot was worth losing half their delegates: New Hampshire, South Carolina, Florida, Arizona, and Michigan.

Colorado and Minnesota emulated Iowa by exploiting the loophole in the RNC’s rule. The penalty applied only to states that selected delegates to the convention. Any state could hold two contests — one, a “beauty contest,” before the March 6 threshold, and a second that selected the actual delegates after it.