Florida Straw Poll was on September 25th. Palin’s announcement was on October 5th.
Pretty clear from the RCP polls that Perry’s fall started with Florida but Cain didn’t overtake Romney until after Palin’s announcement.
Cain’s climb in the polls did not take place until after Palin announced she was not running - this is false.
Cain did not actually overtake Romney in the polls until after Palin announced she was not running - this is true.
Did Cain get a bounce from Palin backers going to his side after Palin’s announcement? I’m sure he did. The point I’m making is that Cain’s rise was not predicated on Palin choosing not to run. Cain was rising - and rising fast -before she made that decision.