No, no groups of Native Americans have special representation in Congress. However, the Indian Citizenship Act of 1924 provided citizenship for Native Americans who were not covered by the Fourteenth Amendment (for instance, because they lived on reservations). As such, they are represented by whomever their local representative and senator are.
You might also be interested in the article linked below on Native American members of Congress.
cherokee
what nation was an amalgam of peoples of both native american and african origin
Native Americans are not a different nation. Our nation is home nation is AMERICA! hello? NATIVE Americans. There have been Natives who have competed in the Olympics. The most famous being Jim Thorpe. Others include Frank Mount Pleasant, Ben Nighthorse Campbell [currently only Native American in Congress; senator of Colorado], Naomi Lang, and a few others. It's not like if we were our own nation we'd get our own land.
The Creek Nation
Richard Pearis became a loyalist when the Provincial Congress would not name him Native American Superintendent.
The phrase 'First Nation' often refers to native people of any given land. Native American or American Indian for example.
the Cherokees
the Navajo is the largest native American nation in north American
the Iroquois
None.
General Ely S. Parker organized many native American nation into a confederation. He was a member of a tribe that was known as Seneca.
No representation in Congress