What will determine the election will be how voters feel about a candidate. Obama appealed to voters desire for change and made them feel like the country has potential. Other candidates have done it in the past as well. Hillary Clinton was completely unmemorable as a candidate. I remember Obama for hope and change and trump for build the wall and make America great again, but what was Hillary's memorable slogan? "I'm with her?"

FOH
Facts dont matter to the electorate as much as actions and feelings. Liberals are in love with facts and have this wet dream where they demolish someone in a debate with some long eloquent answer like on the TV show 'The west wing'. This wont work and it wont matter.
Who ever is running from the Democrat side will have to use some skillfully marketing. Brand trump as a failure and a traitor to the American people. Just like how he brands his opponents someone will have to call him 'Traitor Trump' or 'Tax hike Trump' over and over or 'Donald Do-nothing' emphasizing that he hasn't helped the middle class at all or made life easier for anyone. Whether it's TRUE is irrelevant because with a guy like him if you're not on offense you're on defense.
The successful candidate will have to energize voters and make them believe that the country can be better. The facts and methods of change can come afterwards. If a liberal wants to win they need to kill this fantasy of american politics being some gentlemanly sport with rules and decorum instead of what its always been.