As Lincoln once said:
EnglishCanuck - I'm skeptical. Sherman isn't Grant, and even with Grant's death he doesn't have the incentive to run. He may have political friends, but that doesn't make him good for the job, nor would he be likely to have a sudden 'epiphany' and decide that he is. If he declines then he might throw in a nomination behind another popular general (he's going to want Grant's position more than Johnston's after seeing the Radicals savage him) for the presidency.
If depends if he agrees with the Radicals or not. Maybe he will, maybe he won't. It's a coin toss, but it would be there. He didn't decline a nomination with Lincoln's death, I'm not sure he would do the same with Grant's death but we shall see.
Maybe it will, maybe it won't. Lincoln's death didn't lead to a harsher Reconstruction, and it will depend if Johnston wants Federal troops to be the basis of Reconstruction as well.
They'll certainly be harsher on the traitors (similar to A Glorious Union since public outrage will demand it) but will the Radicals think that anyone will be going far enough for them at this point? That's a hell of a minefield to navigate.
TFSmith121 - As Lincoln once said to Ben Wade, IIRC, when the senator wanted Lincoln to replace McClellan with, "well, anybody!" ... something like:
"Well, it is fine for you to say anybody, senator, but I must have somebody!"
Lincoln's dead, Grant's dead, the rebels have struck, the president is Johnson in all his "glory" and Stanton is secretary of war...oh, and by the way, the acting general-in-chief's father-in-law and brother are both Washington veterans, and everyone knows the next president will be a) an actual Republican, and b) a successful general officer. Gee, I wonder who's going to get the nod, and if he is going to not realize it as well...
Sherman was a brilliantly capable individual, as various and sundry opponents had learned to their embarassment over four and half years of war to the knife. He would know both what was at stake, and the opportunity that presented itself.
I realize there's a perception of Lincoln, Seward, Stanton, and their peers as quaint Nineteenth Century figures, but these were ruthlessly successful men who were elected to and/or functioned in the most politically-charged era in the first true republic of its size in the Western world; thinking they would miss any of this is really pretty questionable, honestly.
They won their war, and their peace, for a reason; it was not a game of chance. They knew exactly what they were doing, and how to do it.
Best,