(Reuters) - President Barack Obama's nominee to oversee Medicare and Medicaid won the backing of a Senate panel on Tuesday, clearing the way for a vote by the full Senate that could make Marilyn Tavenner the programs' first official administrator since 2006. The Senate Finance Committee voted unanimously to endorse Tavenner as head of the U.S. Centers for Medicare and Medicaid Services (CMS). The agency provides health coverage to some 100 million elderly, disabled and poor Americans and also oversees implementation of Obama's signature healthcare reform law, the Affordable Care Act.