What States were loyal to the Confederacy during the US Civil War?

Union States:

Maine, New Hampshire, Vermont, New Jersey, New York, Massachusetts, Rhode Island, Connecticut, Pennsylvania, Ohio, Michigan, Illinois, Indiana, Kansas, Iowa, Minnesota, Wisconsin, Oregon, California, Delaware, Kentucky, Missouri and Maryland.

Note that Delaware, Kentucky, Missouri and Maryland were all Border States who although they did not secede were still not completely loyal to the Union. Washington DC was also a slave-holding border area (but not a state) that remained with the union.

West Virginia (1863) and Nevada (1864) entered the Union during the war.