With just one day remaining before the Iowa caucuses kick off the GOP primary process, Ron Paul dinged surging rival Rick Santorum for being a fiscal liberal.
Paul said the former U.S. Senator from Pennsylvania and staunch social conservative, who has gained traction of late, voted for too much spending while in Congress.
"I mean, have you looked at his record? Go look at his record," Paul told CNN.
Accompanied by son Rand Paul, Ron continued: "He spends too much money. He wasn't leading the charge to slash the budgets and vote against big government."
Rand Paul, who was elected to the U.S. Senator from Kentucky in 2010, added that Santorum's voteing history proved he wasn't a true conservative.
"He voted to double the size of the Department of Education," Rand Paul said. "He voted to expand Medicare and add free drugs for seniors and he has voted for foreign aid."
"Those are not conservative principles ... 77 percent of the American people are opposed to foreign aid and Rick Santorum has voted for it every time it's come down."
Ron Paul, who is running neck-and-neck with Mitt Romney and Santorum in Iowa, again addressed a potential third-party bid should he fail to win the GOP nomination.
"I have no plans in doing that," Paul said. "Tomorrow is a big day. We'll see what happens but I have no intention of doing that, no plans and no desire."