When Romney talks about small business, remember that the following entities count as “small businesses” according to his numbers:

• Enterprise Products Partners, L.P., a Fortune 500 pipeline company worth $34 billion whose PAC gives generously to Republicans.
• Kohlberg Kravis Roberts & Co., the original “Barbarians at the Gate,” a buyout firm worth $61.5 billion that is currently accused of working with Romney’s old firm, Bain Capital, and others to rig bids for companies they wanted to flip.
• McIlhenney Co., the Tabasco maker, with $250 million in revenue in 2007. Their president is the S-corp lobby’s chairman.

Quoted from this Mother Jones article, which explains that these corporations, and many others, use pass-through loopholes to pay taxes as small businesses—and pay zero corporate taxes.

So when Romney suggests that Obama’s plan will hurt small business, he’s really afraid that these large corporations might come slightly closer to paying the taxes they rightfully owe.