UPDATE! Number 10 on my prevouisly posted list, an organization called the Wilderness Society has anti ORV stuff on their front page
http://www.wilderness.orgI did some more research and discovered that a a lot more money, literally millions of dollars is being donated to campaigns under the private names of some of the people who work for and/or run the organizations on this list, as well as the organizations who are advocating land closures all over the country. The details were too numerous to list but the pattern is the same. I did not do the math but if I added all of the numbers for what I was able to find I'd bet the top 20 recipient list would remain the same. Most of the list is made up of Senators and Congressman in the area's of interest, (California, Colorado, Utah, etc) but the top 2 are presidential candidates.
I guess they do this to disguise the fact that their not for profit organizations are promoting certain candidates.