John Giles — the longtime Republican mayor of Mesa, Arizona — is not only throwing his support behind Vice President Kamala Harris, but he’s confronting his party directly for being in thrall to former President Donald Trump. Both Harris and her running mate, Minnesota Democratic Governor Tim Walz, are campaigning in the Grand Canyon State on Friday night in front of a massive audience of approximately 20,000 supporters in the Phoenix suburb of Glendale. Giles spoke ahead of Harris and Walz to warm up the crowd, and launched right into an attack on both Trump and on his own party. “As you may …