LAS VEGAS (AP) — Democrat Steven Horsford and Republican Danny Tarkanian traded verbal jabs in a testy first debate for Nevada’s newest congressional seat. Horsford, the state Senate majority leader, used the Thursday night contest, staged on the show of political commentator Jon Ralston, to paint his opponent as extreme and link him to GOP vice presidential candidate Paul Ryan’s controversial national budget proposal.“What I am not going to do is do what my opponent is proposing, which is to support a Ryan budget which would turn Medicare into a voucher program, all to give a tax break to wealthy …