For those more vintage-thinking, I found the following on Classic Reload, a website for older video games:
Power Politics: The Presidential Election Game (1992), allowing to either create a candidate or to reuse one from the past 30 years to run. The player has to set his schedule, choose a VP, decide on the issues and even use dirty tricks in order to earn the support needed to get enough money to run.
President Elect (1988 edition of game released on 1981), allowing to choose Historical runs (1960 to 1984-1988) or Ahistorical ones, using around 69 hypothetical candidates such as Jesse Helms, Robert Byrd or Orrin Hatch. Here, the VP is merely a modifier denoting a geographical origin. Campaign runs for nine weeks. More about this game here - manual here for the copy protection.
I was reminded of the good old days when all we had to worry about was binders full of women - decided to attempt a world where Romney didn't make the mistakes that cost him 2012, plus a single populist answer on farming subsidies which I credit for winning me Iowa. Overall 285-253 Ev, 50%-49%.
Click to see the Electoral College map from my game, and then try it yourself!
Not bad. I got the combined Thurmond and Wallace national popular vote percentage up to 11%. Also, while Truman got only 40.8%, nine points behind how he did IOTL, Dewey's national popular vote share went up by only 2%, so most of the defections from Truman were to Thurmond and Wallace.
Interesting and somewhat random electoral map.
This wasn't strictly a self-sabotage, the idea was for Truman to run a competent campaign while going out of his way to piss off segregationists and the left. IOTL, he tacked left and got the Wallace vote down to under 3%.
Dukakis/Jackson on normal. Did well in the debate, never really make a bad choice on any other question...still lost by over 200 electoral votes. As often seems to happen, the final polls were a bit too friendly.