Six Senate Democrats urged U.S. News & World Report last week to overhaul how it ranks colleges by giving more credit to those that do the most for underrepresented and disadvantaged students “instead of the privileged few.”

In a letter to Brian Kelly, the magazine’s editor and chief content officer, the senators noted revisions U.S. News made this year to recognize schools that boost social mobility for students from lower-income families. But they said much more could be done to a system that tends to reward certain prestigious private colleges and universities year after year.

“As the leading mass media ranking outlet, we fear U.S. News continues to create a perverse incentive for schools to adopt or maintain policies that perpetuate social and economic inequalities,” the senators wrote, according to a news release from Sen. Christopher Coons of Delaware. Other signers, in addition to Coons, are Sens. Cory Booker of New Jersey, Brian Schatz of Hawaii, Kamala Harris of California, Christopher Murphy of Connecticut and Tammy Baldwin of Wisconsin.

Kelly responded in a letter posted on the magazine’s website. It says, in part, “There is an active debate about how to best measure quality in education, in which we play a part. As always, we engage college and university officials and leaders in education policy and quality metrics on an ongoing basis. Those discussions could include members of the Senate — on an informal basis, of course.”