Hillary Clinton's campaign insisted Saturday it is not sitting on any scandalous information about rival Barack Obama, after conservative columnist Robert Novak wrote that the Democratic frontrunner was holding on to a secret that could wound Obama's campaign.

Novak wrote in a three-paragraph item Saturday that "agents of Sen. Hillary Clinton are spreading the word in Democratic circles that she has scandalous information about her principal opponent for the party's nomination, Sen. Barack Obama, but has decided not to use it."

Novak wrote that the nature of the alleged scandal is not known but "this word-of-mouth among Democrats makes Obama look vulnerable and Clinton look prudent."

Click here to read the Novak article.

Clinton spokesman Jay Carson said "we have absolutely no idea what he's talking about. ... We have no contact with Bob Novak; we have no idea what this column is based on."

Asked if the campaign had any secret information about Obama, he said, "No. No, we don't."

Carson also scolded Obama for "walking right into a Republican trap," after Obama personally challenged Clinton to come forward with any scandalous information she has about him — or admit she has nothing.

"The (article) did not identify these agents, nor did it reveal the nature of the charge," Obama said in a written statement. "It was devoid of facts, but heavy on innuendo and insinuation of the sort to which we've become all too accustomed in our politics these past two decades.

"If the purpose of this shameless item was to daunt or discourage me or supporters of our campaign from challenging and changing the politics of Washington, it will fail. In fact, it will only serve to steel our resolve.

"But in the interest of our party, and her own reputation, Sen. Clinton should either make public any and all information referred to in the item, or concede the truth: that there is none. She of all people, having complained so often about the politics of personal destruction, should move quickly to either stand by or renounce these tactics."

Obama even described the alleged smear as "old 'Swift Boat' politics," a reference to the negative ads questioning presidential candidate John Kerry's military record in 2004. Interestingly, Bill Clinton made the same reference during a speech in Las Vegas in early November in describing attacks on his wife with regard to her position on driver's licenses for illegal immigrants.

The atmosphere among the Democratic candidates has been tense in recent weeks, as Obama and former North Carolina Sen. John Edwards have sought to chip away at Clinton's gaping lead in the national polls.

Clinton stumbled after giving a confusing answer about the driver's license question at a recent debate in Philadelphia, but at the following debate on Thursday in Las Vegas Clinton turned the tables back on her opponents, challenging their records on health care and other issues, as well as accusing them of "throwing mud."

The sniping has led Republicans to criticize the Democratic race.

Carson said Saturday that Obama chose to "parrot Republican talking points" in his statement on the Novak article.

"Bob Novak is a Republican columnist ... a Democratic candidate should be smart enough not to fall into a trap he's set for Democrats to go after each other," he said. "If you don't know how to avoid that in the primary, how are you going to avoid it in the general (election)?"

Obama Campaign Manager David Plouffe rejected that suggestion.

"The Clinton campaign has admitted that they do not possess the scandalous information in question and we take them at their word," he said in a statement. "But what we don't accept is their assertion that this is somehow falling for Republican tricks. This is exactly the kind of smear politics Democrats need to fight back on, regardless of the source or the party. Democrats should know that when Barack Obama is their nominee, he will not allow the Swift boat politics of fear and diversion to prevail in this campaign."

FOX News' Aaron Bruns contributed to this report.