He changed from Republican to "Independent" quite some time ago. He only spent six years as a Republican However, since 2007 (eleven years) he's been a registered "Independent".
I believe that he's disappointed that polling shows that 78% of Independents support the Second Amendment and over 80% of Independents support Free Speech ... He figured that he needed a home where others felt the same way as he. Take guns from everyone but HIS bodyguards and restrict speech in a very draconian fashion. That's what the Democrat Party stands for ... and Micky will feel right at home.
His eleven years, as an Independent, simply could not sway opinions and beliefs .... he had to go where he could.