I think the problem that faced Atari Democrat -- and the reason why I think any of them would have faced similar problems as the Duke, esp. in the frenzied media environment of 1988 -- was a complete lack of emotional connection to the public at large. Much of Dukakis' initial lead was because a) Iran-Contra was still in many people's minds and b) GHWB was distrusted by conservatives after his attempting to position himself as a moderate Republican in 1980. Even Hart (who represented "new ideas") never convinced many people he was the neo-JFK he was trying to portray himself as. Indeed, in the NYT's coverage of the speeches at the 1984 DNC they said of Hart's speech:Of course Reagan would have won decisively. I don't think being an Atari Democrat hurt Dukakis: if anything it was an advantage that gave him an initial polling lead. Rather Dukakis lost due to the good economy and his own missteps in the general election.
Gary Hart put forward a speech to be played back in four years which was unsatisfying now; he tried to get in too many of his stump themes. Speech delivered at a constant pace and without break in tone, making delivery monotonous. ''Nostalgia is not a program,'' a good shot; but old-fashioned slams at a ''gang of greedy polluters'' and ''toxic terrorists'' marred the cerebral yuppie approach. Grade: B minus.
I think Hart himself recognized this, which is why three years later the NYT was talking about how Hart was becoming a more 'open' candidate.
https://www.nytimes.com/1987/05/03/magazine/garry-hart-the-elusive-front-runner.html
Yes, Hart would definitely not pledge to raise taxes (I'm almost surprised that someone like Mondale, who didn't have an ounce of charisma, thought he could pull that off). I think he'd actually end up losing by an even bigger landslide -- Mondale mostly won Minnesota because of his home state advantage, and even that by an extremely narrow margin. Hart's home state of Colorado was a strongly Republican state; it voted for Reagan 63-35. Hart might actually only end up winning D.C.Hart being a more moderate Democrat would prevent Reagan from tying him to the Carter era, I also doubt that Hart would open his campaign by promising to raise taxes as Mondale did. However Hart would still lose.