Yes, if I had to mythologize someone from US history, it would absolutely be Lincoln. The re-integration of the South after the war probably would have gone dramatically differently had he not been assassinated, and who knows what long-term impact that might've had.
Tragically, Lincoln made a liberal democracy out of a democratic republic. More tragically, Washington made a democratic republic out of a constitutional monarchy.
Heck, we might still be a liberal democracy.