Lots of people wouldn't put the slaveowner Washington in their top 4...
Citation needed. Most Americans who are not history nerds, if pressed, could name about 5 Presidents. Washington is definitely going to be in everybody's top 4 because they've heard of him their entire life. Ditto for Lincoln. Democrats will probably add Clinton to their favorites. Republicans will add Reagan. And, of course, most people are aware of Bush and Obama but nobody wants to claim either as a favorite at the moment.
In any case, while I won't defend Washington's practice of slavery, he, at least, had the decency to set them free in his will, something Jefferson did not do. Most of them came from his wife anyway. Jefferson, on the other hand, has the whole Sally Hemmings situation to account for. Owning and having an affair with (she was a slave; I really don't think it'd wrong to substitute the word
rape here) his
dead wife's half sister is something else altogether.