Sen. Susan Collins (R-Maine) ruled out serving as the next homeland security secretary Tuesday and offered up a suggestion on who President Obama should tap to lead the Department of Homeland Security.

Sen. Susan Collins (R-Maine). (Post)

"The White House has not contacted me, I do not expect to be contacted by the White House and I am very happy being senator from Maine and I'm fully committed to seeking reelection," Collins told reporters Tuesday.

Instead, Collins suggested that President Obama nominate former Coast Guard Commandant Thad W. Allen to oversee DHS and its 22 disparate agencies.

"I saw his work with [Hurricane] Katrina and with other disasters -- the BP disaster -- and I think very highly of him," she said.

Collins and Allen have been mentioned as possible successors to Homeland Security Secretary Janet Napolitano, who announced last week that she is stepping down in September to lead the University of California system.

Collins previously served as the ranking Republican on the Senate Homeland Security and Governmental Affairs Committee and works frequently with Democrats on domestic and foreign policy concerns.

First elected to the U.S. Senate in 1996, Collins is seeking a fourth term next year. Democrats might have liked to see Collins take the helm of DHS, because it would have put her Senate seat in play during next year's elections.

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