"We did?” Santorum asked. “You won!” someone offstage said as the crowd cheered.

Even Rick Santorum seems surprised to learn he'd swept two southern primaries, and he summed up his showing perfectly…with just four words:

"We did it again,” Santorum said.

Yes he did. And that means Mitt Romney did it again too…by failing again to win a primary that might finally prove he is indeed inevitable.

Instead, Romney's inevitability became a punch line for his opponents:

"If you're the frontrunner and you keep coming in third, you're not much of a frontrunner. The elite media's effort to convince the nation that Mitt Romney is inevitable just collapsed," Newt Gingrich said.

"For someone who thinks this race is inevitable he's spent a whole lot of money against me for being inevitable," Santorum said.

Still, Romney can–and does–give himself a lot of credit for winning delegates while he's losing primaries…and he suggests Santorum will never catch up:

"Well he's far behind in the delegate count. He's far behind in the popular vote count. Ah, if you look at the math of how many delegates he'd have to win to become the nominee, it's a very difficult road for him," Romney said.

But, after yesterday, Romney's main selling point is getting stale:

"I'm the one guy in this race who can beat Barack Obama," Romney claimed.

Maybe. But can he beat Rick Santorum to get the chance? Yesterday, I believed he would. Today, I'm not so sure.

All I am sure of is that I need to find some new ways to say "grind it out"…because that's what's ahead for Romney and the Republicans.

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