Marcus Aurelius Smith was an American attorney and politician who served eight terms as Arizona Territorial Delegate to Congress and as one of the first two Senators from Arizona. As a Delegate, he was a leader in the effort to gain statehood for Arizona. His non-voting status, however, minimized his influence with only 35 of the 277 bills he introduced into the House of Representatives being signed into law. Lack of a voice in the United States Senate further weakened his efforts as he managed to get Arizona statehood bills passed by the House only to see the legislation blocked in the Senate. Beyond his efforts for statehood, Smith worked to have government buildings constructed and to provide relief to his constituents affected by either man-made or natural misfortunes. His efforts to provide relief to the citizens of Arizona did not extend to the indigenous population, for whom Smith expressed great animosity.

Since Arizona became a U.S. state in 1912, it has sent congressional delegations to the United States Senate and United States House of Representatives. Each state elects two senators to serve for six years, and members of the House to two-year terms. Before becoming a state, the Arizona Territory elected a non-voting delegate at-large to Congress from 1864 to 1912.