Was the "whole" of Marge's persona defined by racist remarks? No. At least it shouldn't be. Yet you seem to think so.
And I say that as one who was no huge fan of hers. But I am not from Cincy, so I didn't completely understand the "affection" many in that local community had for her. And that may be IT. She was not only a very prominent business person in Cincy, but also the owner of the Reds. She had her problems with her peers in the business industry, in which a majority were males. She definitely was a character. But she was also very involved (and close) with the community and it's people. She loved them, and they loved her, warts and all, and regardless of her outspoken and blunt nature.
She was the last person to bring the city a World Series.
And all those variables influenced many within that local community to blindly accept her, and at times, defend her, while seemingly overlooking those many flaws.
No one, including rfs, is saying that her character flaws pr personality are comparable to, or on the same level, as those of Chad Johnson. That is not the issue at all.
Regardless of what you, I, or anyone else, think of Marge (and Chad) they have brought positive things to the community (fans). No one has denied that. And that causes many of those people, at times, to put on "blinders" when that individual's behavior may prove to be an embarrassment.