Major donors have threatened to walk if independent presidential candidate Robert F. KennedyJr. chooses New York Jets quarterback Aaron Rodgers as his running mate, RadarOnline.com has learned. A number of contributors have been vocal about the campaign’s shortcomings, according to a new report, pledging to withdraw their support entirely if he selects the NFL star. RFK Jr. will announce his selection in Oakland on March 26, his campaign confirmed. Kennedy revealed that Rodgers has potential to be his VP pick, but his other top choice is former Minnesota governor and professional wrestler Jess…