I hear you on your irritation with Bachmann, but Cain has gushed more praise at Romney than she has, and Cain has been more sneeringly dismissive of Perry than she has.
Even though I don’t really care for him, I think they should all be following Newt’s direction and trying to sell themselves rather than drag down other Republican candidates. These attacks don’t work - just ask Romney and Perry when they had their little playground fight over illegals. Both clearly did not benefit, and arguably were harmed a bit. Newt comes away the winner every time he takes the media to the woodshed over them playing “gotcha” politics.