Oddly enough, Willkie was a Democrat before he was the Republican nominee. He had been a delegate to the Democratic convention in 1932.
Sez wiki on Wilkie:
Ike, like Wesley Clark, was the head of an alliance and that’s definitely political experience, or at least equivalent to political experience. If you read Wes Clark’s book, his management of the Kosovo war was much more involved with politics than anything else.
Obama? He was only a one-half term state senator.
That’s just silly, Ralph. Obama was both a state senator from Illinois and a US Senator before he was elected President. You know that.
I’m surprised to see him given credit for having been anything more than a community organizer.
Er, no.
And he showed political skill, in not identifying which was which.
I think you’re overestimating the accuracy of the RW bubble.
The question was whether we have ever elected a president with no prior experience. Wendell Wylkie was not elected president–remember?
Grant was enmeshed in politics before his election. Johnson attempted to appoint him as Secretary of War, congress rebuffed him. He was first politically allied with Johnson, but that ill advised appointment drove a wedge between them. Eisenhower is probably the president with the least formal political experience coming into the job, though as always mentioned his role as Supreme Allied Commander was highly political, and at an international level that few other presidents had experienced.
Eisenhower also held several “political” type military jobs after the War, he was military Governor of Germany and Chief of Staff for several years, and then Supreme Commander of NATO.
I’d say Taylor is probably a better choice for lack of political experience. He went almost directly from the military to political office, and his military career involved a lot less high-level “politically adjacent” jobs.
And despite Truman’s quote, Ike actually is probably the most underrated President of the 20th century (note: I say underrated, not perfect.) He was a very capable administrator, and showed a lot of talent in foreign policy and wasn’t bad at domestic policy for someone with no experience in that realm whatsoever.
All the other General-Presidents had failed presidencies; excepting Washington, who I don’t put in that category (since he had relatively significant political experience prior to the Presidency.)
There’s been significant revisionism on Eisenhower’s presidency in recent years, to the point where I now believe he is overrated. The pendulum will be swinging back as it does on almost all presidents. Heck, Harding now has some defenders.
Overrated now? Maybe so. As recently as the 80s/90s I’d say he had become a “forgotten” President. I still have a general feeling that Eisenhower isn’t remembered much at all by the public, albeit he has been the subject of a campaign of renewed interest by historians in recent years. It could be John Adams syndrome to a degree, a prominent historian/writer releases a popular work on his life (David McCullough for Adams) and renews interest in a guy who never deserved a completely terrible reputation, and then a lot of follow-on comes about from people looking to cash in on the renewed interest.
Although a central contention of any effort to revive Adams always required looking at the Alien and Sedition Acts and basically saying that while they were bad he did a lot of other things in his life as a Founding Father/Revolutionary and as a President that make up for it. I tend to think he did do a lot of good, but the initial reason he attained a poor reputation as President were those four laws that made up the A&S acts and frankly, he deserved the criticism he got for them in 1798 and he deserves it now, they are a black mark on his Presidency.
With Eisenhower it’s more difficult, because it’s hard to point to anything like that that he’s particularly known for; Eisenhower was best at using soft power in foreign relations. But by its very nature that doesn’t create the same kind of “hard” record as legislation or other Presidential actions–although I’ve seen it argued that given the President’s limited constitutional role in legislation, the economy, and most of the things voters actually seem to elect President based on, a fair analysis of a President should focus firstly on their success at foreign relations as it is one thing almost wholly in the executive sphere.
I’m not going to argue Eisenhower’s worth as a President, but I do think that whatever the popular opinion of him is worthless, pretty much as it is about every other President. Even when it’s right, as with Washington or Lincoln, it’s not based on anything but air.
Hoover was the U.S. Secretary of Commerce before he became U.S. President, though.
However, generals such as Washington and Eisenhower appear to count for this. 
Actually, Wilson was the Governor of New Jersey, not New York.
Other than some generals, No, I don’t think so. Of course, Chester Arthur might come close to what you are looking for here. After all, the only political job that he held before he became U.S. Vice President (shortly after which he became U.S. President due to James A. Garfield’s assassination) was the Collector of the Port of New York.
Regarding Hoover, does being a Cabinet member count? It’s not an elected office.
Cool, man. You read the thread all the way to post #3. Gold star.