(Reuters) - Presidential hopeful Herman Cain's quirky "smoking ad" may have mystified many Americans, but according to a new Reuters/Ipsos online poll, it has drawn a sharp line between Republicans who identify with the Tea Party and those who don't. The ad, which shows Cain's chief of staff Mark Block puffing on a cigarette for no apparent reason, created enormous Internet buzz this week.Six in 10 of those who strongly identify with the conservative Tea Party movement said they loved or liked the ad.An almost equal percentage of people who self-identified as mainstream Republicans either disliked or hated it.