"If Congress can't cut a corporate welfare subsidy the corporations themselves don't want, what can we cut?" he asked. "Ethanol is a case study of how parochialism trumps progress in Congress. Sooner or later, the Senate will take a vote on this issue."

Earlier in the week, Senate Democrats were hoping to begin voting on amendments by Tuesday afternoon. They originally planned on a vote to repeal tax reporting language in last year's healthcare law (the 1099 repeal) by Tuesday, and to hold votes on Wednesday on amendments to restrict the Environmental Protection Agency's ability to regulate greenhouse gas emissions.

Of the more than 100 amendments to the small-business bill, S. 493, only about a dozen are seen as germane to the bill. Coburn's is not germane, but a political deal could be reached that would allow it to come up as an amendment.