Had to think about it for a while, but I think you answered the question accidentally. It does not have anything to do with voting.
Lets imagine we had a state which got tired of vulnerable and weak social security number. In every place where it is used we replace it a two factor hardware token that include bio-metric data (a photo), issued by the government or institutions like banks that by law are required to follow strict requirement of identification. I think we can both agree that this initiative would not have the goal to make voting harder, nor prevent voting fraud, but rather fix identity theft caused by the weak password-like system of social security numbers.
Lets imagine we had a state which got tired of vulnerable and weak social security number. In every place where it is used we replace it a two factor hardware token that include bio-metric data (a photo), issued by the government or institutions like banks that by law are required to follow strict requirement of identification. I think we can both agree that this initiative would not have the goal to make voting harder, nor prevent voting fraud, but rather fix identity theft caused by the weak password-like system of social security numbers.