By Tim Reid and Kanishka Singh PHOENIX (Reuters) -Democrats took a victory lap on Sunday after retaining control of the U.S. Senate, defying Republican hopes for a “red wave” in the midterm elections, and turned their attention to Georgia where a run-off contest could strengthen their hand in Congress. Democratic leaders portrayed the better-than-expected performance as vindication of their agenda and a rebuke of election denialism and extremist candidates on the right, even as Republicans edged towards control of the House of Representatives with a handful of key races yet to be called. “We w…