On July 17th, the Obama for America Campaign, the Democratic National Committee, and the Ohio Democratic Party filed suit in OH to strike down part of that state’s law governing voting by members of the military. Their suit said that part of the law is "arbitrary" with "no discernible rational basis."
Currently, Ohio allows the public to vote early in-person up until the Friday before the election. Members of the military are given three extra days to do so. While the Democrats may see this as "arbitrary" and having "no discernible rational basis," I think it is entirely reasonable given the demands on servicemen and women’s time and their obligations to their sworn duty.