Think progress Excerpt:
Five senators and 39 representatives received a perfect 100 percent score from the Koch brothers’ Astroturf group Americans For Prosperity for the first half of the 112th Congress. [...]The Kochs were the top contributors to Ron Johnson’s successful campaign to unseat Russ Feingold in 2010.
Johnson ranks in the Top 5 senators in contributions from the Koch empire and returns the favor in votes on Koch-approved legislation, picking up an "A+" grade. Surprisingly, Rep. Paul Ryan picked up only a "B" grade on legislation from Koch despite his proposal to end Medicare among Koch's top priorities. Most Democrats got either D's or F's.