TAMPA, Fla. - Katherine Harris has insisted all along that she could unseat U.S. Sen. Bill Nelson if she could energize the state's strong Republican base. She'll learn Tuesday night how successful that effort has been. Voters heading to the polls Tuesday had a clear choice between Harris, the conservative congresswoman who made her name overseeing Florida's recount in the disputed 2000 election, and Nelson, the staid, centrist Democratic senator who's been spent more than three decades in public office. Harris had her work cut out for her. Nelson has led the Longboat Key congresswoman by as much as 30...