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Marco Rubio speaks to his supporters in Iowa
03:20 - Source: CNN

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Marco Rubio finished third Monday night in Iowa, but he may have won the establishment credibility he needs to stay near the top of the Republican presidential race for the long-term

Rubio will aggressively argue he is the only viable alternative to Trump and Cruz and can unite the party unlike his more divisive rivals

Des Moines, Iowa CNN  —