But Gingrich's double losses Tuesday allowed Santorum to make the most convincing argument to date that it's finally time for divided conservatives to rally behind a single Romney alternative. And it's likely that conservative leaders will join that call in the coming days.
"The time is now for conservatives to pull together," Santorum said.
Even if that happens, it's unlikely to be enough to help Santorum win enough delegates to ultimately defeat Romney. But it's enough to extend the primary battle for weeks, if not months.
It's also enough to prevent Romney from focusing on Obama, the general election and, perhaps even more importantly, raising money for it.
Romney has started facing some financial stresses. His campaign has used an internal pollster only sparingly in recent weeks to cut costs. And Romney hasn't been able to devote as much time to fundraising as he'd like because he's been forced to spend time on the campaign trail as the race moves from state to state.
Should Romney clinch the nomination as expected, the question will become: Can a Republican challenger beat a Democratic incumbent without the GOP base being energized behind his candidacy?
The answer will come in eight months.
Steve Peoples covers the 2012 presidential race for The Associated Press.
An AP News Analysis
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