Both Democrats are benefiting from the alienation some more moderate Arizona Republicans feel toward the hard-line, Trump-led party
Mr. Biden and Mr. Kelly are winning far more registered Republicans — 9 percent and 12 percent — than Mr. Trump and Ms. McSally are capturing registered Democrats.
Long-simmering divisions between conservative and center-right Arizona Republicans have boiled over this year, with Jeff Flake, the former senator, and Cindy McCain, the widow of former Senator John McCain, both endorsing Mr. Biden. At the same time, a far-right Republican who challenged Mr. McCain in his last election, Kelli Ward, has taken over the state’s Republican Party.