The leaders of the Energy and Commerce Committee sent letters to 15 major insurance firms and other groups as part of their probe of Sebelius' involvement in Enroll America, a non-profit group aimed at educating the public about new coverage options following the implementation of President Barack Obama's healthcare reform package, The Hill reported Friday.
Republicans question the propriety of Sebelius soliciting major healthcare players to contribute to the non-profit.
The White House and the Department of Health and Human Services contend Sebelius' actions were legal and similar to measures used to support Medicare Part D under former President George W. Bush.
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