Michael I. Norton is a professor at the Harvard Business School and a co-author of "Happy Money: The Science of Smarter Spending."

When you think of the civil rights movement in the United States, that conjures up images of members of stigmatized groups fighting for equal rights: from African-Americans in the 1950s to women in the 1970s to gays and lesbians today. They sought legal rights equal to those of entrenched and powerful groups: whites, males, heterosexuals.

After these historical associations, you may be surprised by the emergence of an unlikely group of supporters of civil rights. It now may be these very whites who become the most ardent advocates of civil rights – for themselves.

As they become a minority, white Americans may advocate new civil rights laws to protect themselves.

In my research with Sam Sommers at Tufts University, a national sample of Americans reported their beliefs about levels of racism against both whites and blacks in the United States over the last decades. A full 96 percent of white respondents thought that in the 1950s, there was more racism against blacks than against whites. When white respondents rated racism in the 2000s, in contrast, more than half – 51 percent – thought there was now more racism against whites than against blacks.

A number of factors have contributed to this belief among whites that they are now the victims of discrimination, including affirmative action policies and changing demographics. If the demographers have it right, it is only a matter of decades before whites are in fact a minority in the United States.

Perhaps most important, our research shows that whites see racism as a zero-sum game, feeling that any gains made by members of minority groups necessarily come at their own expense. In short, as members of traditionally underrepresented groups become the majority, we are likely to see whites call for a renewed emphasis on defending civil rights – the civil rights of white Americans.