If not Taft, who?

Suppose TR had appointed Taft to the Supreme Court at some point in his presidency. Who would TR have chosen to run in 1908 if Taft isn't available? Besides himself I should add.
 
TR would have liked Root, but he would have realized that a conservative Wall Street lawyer was not the best choice for the West and Midwest. Probably the strongest candidate in Taft's absence would have been Hughes, though TR never warmed to him very much.

One interesting possibility: George B. Cortelyou https://en.wikipedia.org/wiki/George_B._Cortelyou Say, TR is impressed by, among other things, Cortelyou's response to the Panic of 1907. (As the Wikipedia article notes, "He eased the crisis by depositing large amounts of government funds in national banks and buying government bonds. To prevent further crises, Cortelyou advocated a more elastic currency and recommended the creation of a central banking system.") Cortelyou had also served as an efficient chairman of the Republican National Committee--certainly TR could have no complaints about the 1904 election results!--as Postmaster General, and as Secretary of Commerce and Labor. Earlier he had helped TR reorganize the White House after McKinley's death, turning it into a more professional organization.

If TR decides in favor of Cortelyou, I don't see the Republican National Convention defying TR's will--nor is it likely Bryan will beat him in November.
 
TR would have liked Root, but he would have realized that a conservative Wall Street lawyer was not the best choice for the West and Midwest.

Root was in fact Roosevelt's first choice, but it was for the very reason you mentioned that he decided against supporting Root and picked Taft as his successor instead. IMO, Bryan would at least have a somewhat decent chance of beating Root, albeit only very narrowly.
 
It's not impossible that if TR had pointed to Root and Root were the nominee, he (Root) might have lost a real squeaker to Bryan--and I mean one wherein the winner wasn't known until perhaps the Friday or Saturday after the election. But then, I'd bet Bryan would be a single term president. As naive and inexperienced as he was, it's all but impossible to imagine him as an effective chief executive (think Harding without the corrupt friends and also without advisors like Hughes and Hoover). That paves the way very neatly for TR's return in 1912--at the head of a united GOP, I might add. In this situation, TR would have no difficulty in beating Bryan.

I suggest that it also means the phrase "President Woodrow Wilson" would be strictly a creature of alternate history. IOTL, Wilson pretty much had one shot--1912. If he hadn't gotten the nomination then, by 1916 he'd have been out of elective office for three years and could well have been forgotten.
 
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