People always say that the President is a sucker’s job. You get all the blame and little of the glory. However, is there proof of someone who could’ve run for President and won the office, but chose to be, say, Governor or Speaker of the House?
Current people don’t count since Biden, Paul Ryan, and Warren still could run at some point in the theoretical future.
I can’t think of anyone. It’s a lot harder to identify such a person prior to the current primary based system. Such a candidate would have had to work through smoke filled rooms and all that. And prior to that, it was just “not done” for a candidate to run for the nomination. It was his friends that worked through the smoke filled rooms.
I can’t see there being any possible way of proving that someone who didn’t run would have won, anyway.
I don’t know if you’re answering the question or not, but I’m more focusing on someone that everyone liked but thought “nah, it’s not worth all the hassle” and settled for a quieter life?
I am answering the question.
I can’t think of anyone.
The rest is explanation. For example, there is no proof that Biden, Ryan, or Warren (cited in your OP) would win the presidency should they run for it.
Henry Clay, Daniel Webster, and John Calhoun, all famous and broadly supported, all ran for the Presidency. And lost. If none of them won, how can you prove anyone would?
The closest I can think of is Ross Perot, who dropped out once the mud started flying.
Mario.
Given how Kerry came within one state of beating Bush in '04, I wonder if Gore would’ve by definition had a better shot; he presumably wouldn’t have had unexpected stuff coming at him like Kerry did, since Team Bush presumably hit him with everything they had in '00 – when Gore of course won the popular vote anyway.
Ninjaed while previewing, but my answer is more long-winded, so I’m posting it anyway…
Mario Cuomo springs to mind. He was widely seen as the front-runner for the Democratic nomination in both 1988 and 1992, but ultimately declined to run either time. If he’d been the nominee in '88, could he have defeated George H.W. Bush? Perhaps not, though it seems possible he would have done better than poor Michael Dukakis. But if he’d gone for it in '92…early on in that race, Bush 41 was seen as invincible, but of course we all know how that turned out.
Well, that’s a thought. Certainly a case could be made that anybody would have been better than Dukakis in '88. I think it’s likely that Cuomo would have won the Democratic nomination. Less likely in '92.
Would he have defeated Bush either time? Maybe, maybe not. And that is, I think, what the OP is looking for, a definite lock to have won the Presidency. And there isn’t one.
What about lifelong Congressional politicians who didn’t run for higher office? I immediately thought of Ted Kennedy but forgot he ran in 80.
Not a definite lock at all. I’m writing a paper trying to make a predictive model of who would run for president/why people run for president so finding people that COULD’VE done it but didn’t is really important for trying to find differing variables between the two. I’m just brainstorming right now and asking dopers so I don’t forget anyone on accident 
OK, well that’s an entirely different question than you asked in the OP. Cuomo is definitely an answer to people that could have run and been a serious candidate, but declined to run.
Colin Powell, too.
Colin Powell is a name who was mentioned repeatedly as a potential candidate but had no interest in running.
If you dig deep enough I’d expect that many other generals have been bruited as candidates since WWII. George Marshall and Douglas McArthur were, and so was William Westmoreland. Curtis LeMay and James Stockdale ran as third-party VP nominees so I’m sure some people considered them as presidential candidates.
Other than that just go through lists of people whose names were dropped the year before elections. Most of them never run.
None of them could win, either, so you need to decide which version of your question you’re asking.
Maybe, possibly General Douglas MacArthur could have won if he had run for President in 1952, since he seemed to become even more popular after Truman fired him. But MacArthur (who was interested enough in 1948) chose not to run in 1952, and left the field open for Eisenhower.
OTOH, MacArthur would have been a seriously flawed candidate.
Ben Franklin.
Colin Powell, possibly.
Walter Cronkite?
Note, Ben Franklin wasn’t a possibility. He was already an old, about 80, and somewhat infirm man at the time of the Constitutional Convention of 1787.
ETA: I see I’ve been multiply ninjaed on Powell.
Henry Scoop Jackson, both in 1972 and 1976. Nixons approvals were dropping in 72 until it became clear McGovern would get the nod. Jackson could never have been painted as a surrender to communism like McG was, yet Jackson’s domestic policy was based on popular ideas. Lacked the acid, amnesty and abortion bit. Def woulda had a shot in 1972, and woulda been a shoo-in for 1976. Could picked up the West Coast and CA, red states back then, also the east, and wouldn’t have almost blown it on Playboy with hearty lust.
I think Nelson Rockefeller would have had a good chance.
My knowledge of 19th century history is sorely lacking, but wasn’t wild-eyed pyromaniac William T. Sherman thought to be a good candidate for President until he famously rejected the idea of running?