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Tonight on Hannity & Colmes:

• Nuclear scientists with hidden radiation equipment scoured five major American cities for dirty bombs days before New Year's Eve celebrations -- Cause for alarm? Former N.Y. Mayor Rudy Giuliani answers our questions.

• He beat the odds — From long shot to frontrunner of the hopeful Democrats — But might former Vermont Gov. Howard Dean (search ) be about to learn the only thing harder than taking the lead ... is keeping it?

We'll assess the Democratic race for the nomination with Cheri Jacobus, Republican strategist, and Mary Anne Marsh, Democratic strategist.

• Speaking of Democrats learning lessons ... Sen. Hillary Clinton (search) may be learning the true meaning behind an old adage -- "Open mouth, insert foot." The junior senator from New York's recent 'lame attempt at humor' (as she described it) has put her in some hot water. We'll have the details.

Did she have an innocent lapse of judgment or is the senator guilty of insensitively stereotyping an ethnic group? Linda Chavez of the Center for Equal Opportunity joins the debate.

• FNC's own Oliver North, host of "War Stories," joins us.

All these stories and much more!

Don't miss Hannity & Colmes LIVE this evening at 9 p.m. ET!

--The Associated Press contributed to this report

-All guests and topics subject to change