The researchers found that 2.5 million Americans of Hispanic origin, or approximately 7 percent of the 35 million Americans of Hispanic origin in 2000, changed their race from “some other race” in 2000 to “white” in 2010. An additional 1.3 million people switched in the other direction. A noteworthy but unspecified share of the change came from children who weren’t old enough to fill out a form in 2000, but chose for themselves in 2010.

The data provide new evidence consistent with the theory that Hispanics may assimilate as white Americans, like the Italians or Irish, who were not universally considered to be white. It is particularly significant that the shift toward white identification withstood a decade of debate over immigration and the country’s exploding Hispanic population, which might have been expected to inculcate or reinforce a sense of Hispanic identity, or draw attention to divisions that remain between Hispanics and non-Hispanic white Americans. Research suggests that Hispanics who have experienced discrimination are less likely to identify as white.

The data also call into question whether America is destined to become a so-called minority-majority nation, where whites represent a minority of the nation’s population. Those projections assume that Hispanics aren’t white, but if Hispanics ultimately identify as white Americans, then whites will remain the majority for the foreseeable future.