I have not been on this website for a while. Will Mexicans becomes white? Visiting Mexico many times, what Mexican subgroups are you referring to, because all groups in California especially is represented.
Mexican who look like this, will never be considered "white" in America, and they are definitely not considered "white" from a latin american context.
Obviously these people do not look close to Western Europeans, or even Lebanese and Syrians to be "white", or European by any standards. These people is very well represented in southhern California, they are obviously native influence, they are similar racially to your "red" indians.
However this group of Mexicans are already considered "white", they are represented here in Los Angeles, and Mexico as well.
vs Italians
Some will be considered white, or some case ambigenous, while other will not, because they have to much red Indian characteristics.
Like everywhere else there is a caste systems, which is based on their colonial past. A trip to the museum in Mexico City, give you and idea of the racial caste system that developed in Mexico and other latin american countries.