That’s what Democratic Socialist and Progressive-Democratic Party Presidential candidate Bernie Sanders (I, VT) thinks ought to happen. He couches this as all citizens having a right to vote, “even terrible people.”
Unfortunately, though, Sanders has misunderstood the nature of the social compact, and the Lockean nature of our American social compact.
Certainly, all American citizens ought to be able to vote in American elections. However, felons, by dint of their voluntarily done criminal acts, have placed themselves outside the bounds of our social compact—they’ve made themselves outlaws in several senses of that term. As felons under the terms of our social compact (Locke’s terms went a bit farther), these persons have surrendered a number of their citizen rights: freedom of movement, of keeping/bearing weapons, of association, of communication, and from search and seizure, among others. Felons still can do many of these things, but they are severely restricted in the doing (and in some, completely barred) by the requirements of law and the strictures of the prison in which they’re held as those requirements are executed.
Since felons are outlaws, also, though, they’ve surrendered one more right of citizenship: the right to vote.