It was Rick Santorum, not Mitt Romney, who had the telling line of Tuesday night.

“Game on!” announced the former Pennsylvania senator, as his backers cheered an Iowa Caucus result that made him the conservative “flavor of the month” in the month that actually matters.

Santorum and his crew had plenty to celebrate after Iowa Republicans finished caucusing.

Romney said on the eve of the Iowa Caucus vote that he would win the frst Republican presidential competition.

Instead, the former governor who critics disparage as a “Massachusetts moderate,” ended up in a nip-and-tuck race with Santorum, a self-described “full-spectrum conservative” candidate whose numbers rose only in the last days before Iowans caucused.

After the better part of a decade of camaigning for his party’s presidential nomination, after spending millions of dollars from campaign accounts, and having millions more spent on his behalf by Super PACs, Romney could only manage an eight-vote “victory” over a candidate who just weeks ago was polling less than the margin of error.

That is not the sort of victory that a candidate with Romney’s many advantages can and should relish.

After enjoying all the benefits of a divided opposition throughout the 2012 campaign, the former Massachusetts governor now faces a relatively clearly defined “not-Romney” conservative in the form of Santorum, whose position could actually improve with the exit of Minnesota Congresswoman Michele Bachmann and the decision of Texas Governor Rick Perry to skip the New Hampshire primary. Indeed, as Santorum heads to New Hampshire, he will get an assist from at least one remaining candidate, former House Speaker Newt Gingrich, who finished fourth in Iowa but promised to continue a campaign that now seems to be focused on nothing so much as attacking Romney.

Romney and his aides were spinning their “win” as hard as they could Tuesday night and Wednesday morning. His big “news” was an announcement of support from Arizona Senator John McCain, the party’s 2008 nominee. But McCain, never a favorite of movement conservatives, will do little to secure support from the majority of Republicans who tell pollsters they would like someone, anyone, other than Romney as their nominee.

Could Santorum, a candidate who wasn’t even considered to be in contention a month ago, be that someone? At the very least, Santorum has earned a right to grab for the conservative crown that right-wing activists have always objected to rested on Romney’s head.

As Santorum now grabs for that conservative crown, it will be a lot easier. Candidates who he trailed in the long fight for conservative support, Perry and Bachmann, are now quitting or dialing back their campaigns. Unless they endorse Romney—an unlikely prospect—Santorum should benefit.

Here are some numbers that excite Santorum: combine his Iowa numbers with those of Perry and Bachmann and you get a striking 40 percent of the total vote.

Combine Santorum, Perry and Bachmann backers in New Hampshire polls, and Santorum moves even with or ahead of former Utah Governor John Huntsman, who skipped Iowa to make his stand in the Granite State’s Tuesday primary. And the prospects for a “full-spectrum conservative,” as Santorum refers to himself, get even better in upcoming primary states such as South Carolina.

This is the challenge Romney now faces.

Romney may be claiming a “win,” but the real news from Iowa is that Santorum is now in contention. That does not mean that the former senator from Pennsylvania is likely to be the Republican nominee against President Obama next November. Romney still has a lot of advantages. But it does mean that Romney will have to devote the next few weeks, maybe the next few months, to seeing off a challenge from a credible conservative.

How many Republicans are looking for a not-Romney? A lot, if the Iowa results are any indication.

“No matter how Romney’s establishment allies try to spin it, tonight’s results show conservatives have strengthened their opposition to Mitt Romney’s candidacy,” announced veteran conservative strategist Richard Viguerie. “The fact that conservative candidates garnered three times as many votes as Mitt Romney did speaks volumes about how narrow and shallow Romney’s support is and the likelihood that the nomination will not be settled until the GOP Convention in Tampa.”

Even Republican-leaning pundits acknowledge that there is no enthusiasm for Romney.

Overall Tuesday’s Republican Caucus turnout in Iowa was only slightly better than in 2008. when 119,000 Republicans voted. Remarkably, were it not for the independents—who made up roughly a quarter of this year’s caucus crowd, and who leaned hard toward Paul—the Republican total would have dipped below 100,000. “When you take out the independents who showed up to back Ron Paul, this was actually a lower turnout than Republicans saw in 2008,” said conservative blogger Erick Erickson, who explained that Republicans “don’t particularly care for [Romney].”

Despite the distaste for Romney, Santorum faces an uphill climb. He won’t have Romney’s money or organization.

But Santorum isn’t Romney. That should keep him in contention for weeks, perhaps months. And even if he does not block Romney, Viguerie suggests that the ongoing race could create an opening for another, potentially stronger, conservative to make a late entry into the GOP race. “The vast majority of Republican primary voters want to vote for a principled, small government, constitutional conservative,” said Viguerie. “With 75 percent of the vote available, the door is now open to a new conservative standard bearer who can unite the party in the way Romney has failed to do.”

That may just be Viguerie’s pipedream.

But it is, by any reasonable measure, Romney’s nightmare.

Despite the bravado he displayed Tuesday night, the Iowa results created a serious problem for Romney, who in recent days not only anticipated an Iowa win but tried to switch his focus to attacking Obama. Now, in the face of a steady conservative challenge, Romney will have a hard time taking the fight to Obama.

Obama, for his part, swept the Iowa Democratic caucuses Tuesday night. In roughly a dozen precincts, “uncommitted” slates backed by Occupy activists and the Iowa Health Care Not Warfare Campaign achieved credible finishes.

But the real race was always on the Republican side. And, there, the raw numbers in what was effectively a glorified straw poll of all caucus-goers confirm that the vast majority of Republican caucus voters opposed Romney:

Romney—30,015 for 24.6 percent Santorum—30,007 for 24.5 percent Paul—26,219 for 21.4 percent Gingrich—16,251 for 13.3 percent Perry—12,604 for 10.3 percent Bachmann—6,073 for 5 percent

Network entrance polls had Santorum beating Romney and Paul among Republicans.

Santorum was winning among self-described “very conservative” voters, and among evangelicals.

Paul was winning among self-described “moderates” and “liberals.”

Paul was winning big among independents, who made up almost a quarter of caucus-goers. Among independents who caucused as Republicans Tuesday night, 44 percent were for Paul, 18 percent were for Romney, 13 percent were for Santorum.

Among the roughly one-third of voters who told pollsters this was their first time attending a GOP caucus, Paul led with 37 percent to 21 percent for Santorum and 15 for Perry.

Among voters under age 30, Paul was winning 48 percent, while the oldest candidate was only getting 11 percent among voters over age 65.

Those were encouraging numbers for Paul.

He got a ticket out of Iowa, but that was expected.

Romney also got a ticket out of Iowa, which was also expected.

What was remarkable was that Santorum got the third ticket. So it was that the also-ran finished as a winner.

Santorum leaves Iowa as the not-Romney. And, in a Republican Party that has no taste for Romney, that’s the coveted title.