I think it has less to do with where they get their campaign contributions than it does the mindset of their supporters. Most all energy companies have acknowledged that CO2 emissions are effecting the climate and I suspect Sullivan and Murkowski understand the science as well. They are  simply pandering to those who get their science from Rush and Sean.  On the other hand I still scratch my head at folks who do understand the problem but limit the solutions by taking hydro, nuclear, and natural gas off the table and pretending that a renewables alone can provide the reliable and predictable source of power needed for transmission. You then wind up in situations like Germany where despite huge subsidies for renewables they are burning more coal than ever. This is no excuse for the lack of leadership by our delegation on this issue but it does demonstrate science denial really does cut both ways.