Who can vote in us presidential elections?
American citizens who are 18 or older are usually eligible to vote. (Some ex-criminals are barred from voting.) Advanced registration is required most places and a voter has to go to his assigned polling place.
In all US States of the United States, if you are convicted of a felony and are serving prison time, you cannot vote while in prison. I am not sure about people who have finished their prison time. Perhaps some States may allow a former convict to vote. Another way to lose one's vote in Presidential elections is to move to Washington DC or Puerto Rico. Other US territory's such as the US Virgin Islands…
No. At least not directly. Puerto Rican residents get to vote in presidential primary elections which means they have a proportional say in who will run for president in the Republican and Democratic parties (as well as some of the alternate parties). But Puerto Ricans do not vote in the presidential elections themselves.