Last month, the Obama administration issued important guidance to colleges and universities on how to increase racial diversity on campuses, explaining ways to navigate the narrow legal channel charted by the Supreme Court. The benefits of diversity, the Department of Education said, contribute to “the educational, economic and civic life of this nation.” The administration’s support for such efforts stands in stark contrast to the policy of the George W. Bush administration to discourage them. That difference has played out between the political parties for decades, as it will in this presidential election.

Race-conscious programs in education — affirmative action in college admissions and voluntary integration of public schools — have been embattled for more than 40 years. Since the 1970s, the Supreme Court has restricted the approaches available to remedy racial disparities, but has left room for institutions to consider race in achieving certain broader aims.

The war has not ended, however, and three notable lawsuits around the country show the continuing controversy. In March, the United States Court of Appeals for the Sixth Circuit will reconsider Michigan’s ban on affirmative action in public university admissions, which a three-judge panel of the court struck down last summer. By prohibiting race-conscious admissions under the Michigan Constitution, the court said, the ban “reorders the political process in Michigan to place special burdens on minority interests.”

In the Fifth Circuit, a three-judge panel a year ago upheld the use of race as a factor in admissions at the University of Texas at Austin. Four-fifths of students there are admitted as graduates in the top 10 percent of their high school classes. But one-fifth are admitted based on individual assessments, including race as a factor, and this program is being challenged. The university is waiting to hear whether the Supreme Court will review that decision.

In the Ninth Circuit next month, a three-judge panel will hear an appeal from a district court decision to dismiss a challenge to California’s Proposition 209, which outlawed race-conscious admissions in 1996.

Any or all of these cases could end up before the Supreme Court, on which four conservatives have made clear that they would make illegal even narrowly tailored diversity programs. Chief Justice John Roberts Jr. spoke for himself and Justices Antonin Scalia, Clarence Thomas and Samuel Alito Jr. in 2007 when he wrote in an opinion, “The way to stop discrimination on the basis of race is to stop discriminating on the basis of race.”

Justice Anthony Kennedy, while no fan of affirmative action, has in past decisions supported some use of race in certain situations. The question is whether he will move further to the right and reject those uses as well.

Leaders of universities, corporations and other institutions fear that the conservative majority will overrule Grutter v. Bollinger, the 2003 case that upheld the right of a public law school to consider race in admissions to achieve the benefits of a diverse student body. In endorsing that educational need, Justice Sandra Day O’Connor, writing for the court’s majority, noted that perhaps in 25 years race-conscious policies would no longer be needed.

This country is still very far from that goal. The push by Republican politicians and conservative justices to eliminate efforts to ensure diversity on campuses are squarely at odds with America’s racial history. With the court’s makeup likely to change in the next four years, the presidential election could determine how long such crucial efforts will last.