McCain managed to keep the open primary until after his last election. Let’s hope we can get rid of that. Dems vote for McCain and now will also vote for Flake. Neither one could get elected by republicans.
Arizona does not have an open primary - Democrats cannot vote in the Republican primary, though “independents” can pick either party’s primary to vote in. McCain won because Hayworth was not exactly conservative on a number of issues and McCain crushed him under tons of cash, not to mention he had Sarah Palin campaigning along side him during that primary. It didn’t help Hayworth that he appeared in an infomercial pushing a questionable product that McCain was also able to exploit.