PHOENIX Joe Arpaio is trying to win back the sheriffs post in metro Phoenix that he held for 24 years, facing his former second-in-command in the Aug. 4 Republican primary in what has become his second comeback bid. The winner will go to face Democrat Paul Penzone, who crushed Arpaio in 2016 and is running unopposed in his primary. I am not Joe Arpaio.Mike ONeil, a longtime Arizona pollster who has followed Arpaios career, believes general election voters would vote down Arpaio. But he said its an open question whether primary voters his most faithful supporters would reject him. In a Republican primary, its anybodys guess, ONeil said.