WASHINGTON - (AP) - The U.S. Senate has passed President BarackObama's landmark health care overhaul in a climactic Christmas Evevote, extending medical insurance to 30 million Americans. The bill requires nearly all Americans to buy insurance andforbids insurance companies from denying coverage based onpatients' pre-existing conditions. The 60-39 vote on a cold morning capped months of arduousnegotiations and 24 days of floor debate. It followed a successionof failures by past Congresses to get to this point. Vice PresidentJoe Biden presided as 58 Democrats and two independents voted"yes." Republicans unanimously voted "no." The Senate's bill must still be merged with legislation passedby the House before Obama could sign a final bill in the new year. There are significant differences between the two measures butDemocrats say they've come too far now to fail. Vicki Kennedy, the widow of the late Massachusetts Sen. EdwardKennedy, who made health reform his life's work, watched the votefrom the gallery. "This morning isn't the end of the process, it's merely thebeginning. We'll continue to build on this success to improve ourhealth system even more," Majority Leader Harry Reid said beforethe vote. "But that process cannot begin unless we start today ...There may not be a next time." The House passed its own measure in November. The White Houseand Congress have now come further toward the goal of acomprehensive overhaul of the nation's health care system than anyof their predecessors.