Lieberman, who was the Democratic vice presidential nominee in 2000, was a leading congressional negotiator in writing the law that created a national intelligence director.

Bush also needs to replace Tom Ridge, who is leaving the job of homeland security secretary. Bush's first choice, former New York City Police Commissioner Bernard Kerik, withdrew in controversy.

"I do have some fundamental agreements with President Bush on America's foreign policy, and I want to give bipartisan support to those elements of the foreign policy, like what we're doing in Iraq today," said Lieberman, D-Conn. "But I think I can do it better in the United States Senate."

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Editor's note: