Santorum: I '100 Percent' Endorse Donald Trump For President (VIDEO)

Rick Santorum on Fox News Greta tonight says his main concern with the next president is who he will nominate to the Supreme Court. In a prior conversation with Trump, he asked for a list of who Trump would name to the High Court and if he approved, Trump would get an endorsement from Santorum. "The most important issue right now is to preserve the Constitution.” Santorum said.

Back a few months ago, Santorum endorsed Marco Rubio in the primary, tonight he's all in for Trump. Here's why-

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