Political contributions from drug maker Merck to Texas Gov. Rick Perry are substantially higher than he said at Monday night's CNN/Tea Party Express debate.

Perry low-balled the number, saying the contribution was just $5,000. But since 2001. Merck has given Perry a total of $28,500.

In the debate, Rep. Michele Bachmann accused Perry of mandating a statewide innoculation program using the Merck-made vaccine Gardasil after the pharmaceutical giant gave money for his 2006 campaign.

Perry said the contribution was just $5,000 and said: "And if you're saying I can be bought for five thousand — I'm offended." But the 2006 contribution was actually $6,000.

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