Citizenship of the United States
A person who is considered a citizen by more than one nation has "dual citizenship". It is possible for a United States citizen to have dual citizenship; this can be achieved in various ways, such as by birth in the United States to a parent who is a citizen of a foreign country (or in certain circumstances the foreign nationality may be transmitted even by a grandparent) by birth in another country to a parent(s) who is/are a United States citizen/s, or by having parents who are citizens of different countries. Anyone who becomes a naturalized U.S. citizen is required to renounce any prior "allegiance" to other countries during the naturalization ceremony; however, this renunciation of allegiance renunciation of citizenship to those countries.
United States nationality law
Adult citizens of the United States who are residents of one of the 50 states or the District of Columbia (Washington, D.C.) have the right to participate in the political system of the United States, as well as their state and local governments, (with most states having restrictions on voting by persons convicted of felonies, and a federal constitutional prohibition on naturalized persons running for President and Vice President of the United States), to be represented and protected abroad by the United States (through U.S. embassies and consulates), and to live in the United States and certain territories without any immigration requirements.
Felons can vote in over 40 states, and in at least 2 while incarcerated. Felons can also serve jury duty if approved.