Like more than a dozen other stragglers in the Republican presidential race, Sen. Marco Rubio of Florida has been counting on widely viewed televised debates to lift him into the top tier of candidates.
His sure-footed performance in Wednesday's CNBC debate was Rubio's strongest so far, with a withering retort at the ready when his archrival Jeb Bush assailed him for skipping Senate votes while running for president.
But in a volatile and unpredictable nominating contest, the question for Rubio remains: Was it enough?
Rivals acknowledged that Rubio stood out on the University of Colorado stage among the cluster of seasoned politicians jostling to outmaneuver front-runners Donald Trump and Ben Carson.
"He's always really well-prepared," Russ Schriefer, a media advisor to New Jersey Gov. Chris Christie, said of Rubio.
But the 44-year-old first-term senator still must battle his image as a "man in a hurry" to get ahead, he said.
"I think he had a good answer to that question" — that troubled times demanded his immediate intercession -- "but it's going to linger for a while, and I don't think that's something he can easily put to bed," Schriefer said.
Bush mocked Rubio for showing up so rarely in the Senate that he's enjoying "a French workweek" of just three days.
"I don't remember you ever complaining about John McCain's vote record," Rubio said of the 2008 Republican presidential nominee. "The only reason why you're doing it now is because we're running for the same position, and someone has convinced you that attacking me is going to help you."
Rubio had two other strong debate performances that drew considerable praise, but they failed to translate into meaningful new support in polls or fundraising.
Another candidate, former Hewlett-Packard chief executive Carly Fiorina, surged in the polls after two strong debate performances, but quickly fell back into the bottom ranks.
Rubio campaign manager Terry Sullivan, perhaps mindful of those precedents, tried to diminish expectations, saying the senator would see no such surge.
"It's checking another box – can he take a punch, and how does he handle it," Sullivan said. "And he took some punches and returned them just as good or even better than he got them."
Sullivan also was cautious not to gloat over Bush's enduring difficulties.
"There's no need to pile on Gov. Bush after his performance tonight," he said – his pity speaking volumes about where the two candidates find themselves in the debate's aftermath. "I think the interaction between he and Marco speaks for itself."
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