Story highlights The supporter says Trump's insistence on standing by his wiretap allegations poses a problem

"We're not in an election anymore, and it's not his opponent he's throwing off"

(CNN) Former Republican presidential candidate Rick Santorum made it clear Thursday night that he is not a fan of President Trump's repeated allegations that former President Obama wiretapped him, warning Trump is only "hurting himself."

The former Pennsylvania senator supported Donald Trump for president and has backed him on a variety of issues, ranging from trade and immigration to Trump's choice for the Supreme Court.

But during an appearance on CNN's Erin Burnett "Outfront," Santorum warned that Trump's insistence on standing by his wiretap allegations poses a problem for the President.

"We're not in an election anymore, and it's not his opponent he's throwing off," Santorum said. "I think it's him that he's throwing off."

"In this case, he has no opponent," Santorum said. "And who he's hurting is not a rival, he's hurting himself, because he's now the president and it doesn't matter whether he blames Barack Obama or not. People don't care about Barack Obama anymore. They care about one person. They care about the president, and he's the president."

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