In 1906, Congress passed an act that would enable New Mexico and Arizona to become one large state. Arizona residents voted against the act, while New Mexicans voted for it. Not until 1912 were the opposing forces reconciled, and New Mexico was admitted to the Union as the 47th state. At that time, it had a population of 330,000. Shortly afterward, the discovery of oil and gas, together with increasing tourism, opened the state for rapid expansion.