Herman Cain, a former corporate executive, bested other Republican presidential candidates in a straw poll of Florida Republican activists Saturday, a blow to the once-surging campaign of Texas Gov. Rick Perry, which had lobbied hard for victory.

Mr. Perry was the only top-tier candidate to declare himself all-in for the straw poll, organized by the Republican Party of Florida and held in Orlando. His supporters had targeted the 3,500 delegates, and Mr. Perry himself had poked some other candidates for side-stepping the event.