House Majority Whip James Clyburn (D-S.C.) said Sunday that Democratic presidential candidate Tom Steyer has been surging in recent South Carolina polls because the billionaire candidate is spending money on ad buys throughout the state.

"I've always said money is a mother's milk of politics," Clyburn said on CNN's "State of the Union," when asked about Steyer's rise.

"He has money and he has been spending it, I think that will always make a difference."

Steyer, a billionaire philanthropist, did not perform in the top tier of the race in the first two nominating states, but he has staked much of his campaign on how he does in South Carolina.

Recent polling has shown Steyer in third place in the state, compared to support just above 1 percent nationally.