A GOP operative launched the committee after the rapper revealed presidential aspirations.
The top staffer has jumped to Rick Santorum's campaign.
Paul's 2016 GOP rival, Gov. Scott Walker, has called it a "legitimate" idea.
"We are not engaged here in demagoguery. We’re not engaged in racist attacks," Sanders said.
"Forget love, it’s time to get tough!” the real estate mogul declared.
A new survey finds Trump and Carson taking 23 percent support each.
Walker hammers Bush for not vowing to tear up the Iran deal.
The Illinois Republican rejects the contention that Bush looks "joyless and awkward."
Rebecca Shabad 08/31/15 10:19 AM EDT
In a shutdown, 41 percent would blame the GOP, while a third would blame Dems.
"We demand action, not words, from those who purport to stand with us," the group said.