WASHINGTON (CNN) -- Former House Majority Leader Tom DeLay told CNN Wednesday he does not support the front-runners in the race for the GOP presidential nomination and warned fellow Republicans that Sen. Hillary Clinton will likely be the next president if his party abandons its core beliefs.

Though DeLay called Rudy Giuliani an obvious "leader" who may be able to win over some social conservatives, the Texas Republican said he would not vote for the former New York City mayor, even if he were to win the GOP nomination.

"I can't vote for somebody that's for abortion," DeLay told CNN's Wolf Blitzer on the Situation Room. "I never have, and I never will."

DeLay also cited Giuliani's support of gun control and gay rights as reasons social conservatives might turn away from the New York Republican.

DeLay had dire predictions to make about Sen. John McCain's second bid for the White House as well, citing vigorous opposition to the Arizona Republican's championing of campaign finance reform.

"I don't think he'll get very far because he is not -- does not reflect the vast majority of the party," DeLay said. "There's a lot of conservatives that fault him for our situation right now because of McCain-Feingold...the lack of understanding about what the constitution guarantees and rights it guarantees."

DeLay's favorite candidate in the race is former Arkansas Gov. Mike Huckabee, because he said the two share almost an "identical" worldview.

But DeLay also acknowledged that Clinton "built the biggest, most powerful coalition that I've ever witnessed in my lifetime," and warned that the New York Democrat will be nearly unbeatable unless the GOP can adequately energize its base.

"They need to go back and show their base that they haven't lost their principle, they haven't lost their way -- that they will fight for what they believe in," DeLay said.