FDR was reelected in 44 and would not stand for reelection, and coronation, until 48. I am not so sure Patton would have been his adversary. Truman was always worried about MacArthur and of course that never came to fruition either as MacArthur lost the first primary he was in effectively killing any hope he could win.
That said, I do believe there was a conspiracy to take him out. He openly was using former Nazi party members. While our OSS was also using these same people, they did not wish it to be become an issue after the war ended. So, I believe our own government had more to do with his demise than did the soviets although I would not put it past them. They did try to take out Gen Haig years later when he was in charge of SHAPE. Interestingly, they tried to kill him while he was in a vehicle.
The media hated him which was a pretty good sign.
“FDR was reelected in 44 and would not stand for reelection, and coronation, until 48. I am not so sure Patton would have been his adversary”
FDR kicked the bucket in the spring of ‘45. Wait that was impossible, I mean he bought the farm ‘45.