The answer is that supporters marched in New York. The most of them were black students worried about the end of racial quota for Universities and protesting against what was called "reversed racism".
According to them, that was a plan from the government to ban the black rights accusing directly Jimmy Carter of being racist.
The supporters had the help of other civil rights activists such as Asian-Americans Women's Labour Union, National Committee to Overturn the Bakke decision, The National Lawyers Guild, the Black American Law Students Association and People's Alliance.
Also gathered there was the US Communist Party, Youth Against War and Fascism, Central Labour Council among others. Official numbers of demonstrators was published by the US Park Police as 15.000 people.