(CNN) South Carolina Republican Mark Sanford already has one supporter in Congress for his potential long-shot bid to challenge President Donald Trump in the Republican presidential primary: newly independent Michigan Rep. Justin Amash.

Amash, who left the Republican Party in early July and has repeatedly declined to rule out a presidential bid of his own , told CNN that Sanford "would be a great candidate."

"I know Mark. He's thoughtful, he's humble, he's learned from his mistakes and grown, and I think we really need a person like that in the White House," Amash said.

"My perspective is that the party is lost for quite a while and that this party system is corrosive, and I don't think it can be redeemed anytime soon," he added. "But it's good to have voices out there. And the more voices you have, the more likely a miracle could happen."

Amash again brushed off questions about his own presidential ambitions, saying he was focused on providing independent representation for his constituents in Congress.

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