I suppose there may be an equal protection (14th Amendment) argument to be made in this instance, as in Bush v. Gore (and, indeed, in Romer), but I haven't studied the details here at all.
Good points.
“No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.”