The attack on ObamaCare was that Congress does not have the power under the Commerce Clause to force a private citizen into a private contractual relationship. If such a thing is permitted to stand the anti-ObamaCare forces argue there will be no limit to Congress's power in the future.
The real estate agent had to go door-to-door in the apartment building we wanted to rent asking if it was OK for this interracial family - my mom is white and I was a 1-year-old half-African kid - to live in the apartment building.