On this day, Jan. 21, 1911, New Mexico voters ratified the state constitution. One year later, on Jan. 6, 1912, New Mexico was admitted to the Union as the 47th state.

This was the longest wait between territorial organization and statehood for any U.S. state. Congress established New Mexico as a U.S. territory in 1850, and it was admitted as a state more than 61 years later, in 1912.

Other U.S. territories with some of the longest waits for statehood included Arizona (49 years, becoming the 48th state in 1912), Alaska (47 years, becoming the 49th state in 1959), and Hawaii (59 years, becoming the 50th state in 1959).

After becoming a U.S. territory in 1850, New Mexico drafted four constitutions. Voters approved the first constitution in 1850, but Congress did not admit New Mexico as a state. Voters later rejected constitutions drafted during conventions held in 1872 and 1889.

On June 20, 1910, Congress authorized qualified electors in the New Mexico Territory to vote for and choose delegates for the constitutional convention in order to draft another constitution. Delegates gathered in Santa Fe on October 3, 1910, to write the constitution. On November 21, 1910, the convention voted 79-18 to adopt the proposed constitution.

Voters needed to ratify the new constitution. On Jan. 21, 1911, voters approved the new constitution by 70.3% to 29.7%. The new constitution included many elements, including the veto referendum process in the state, which allows voters to uphold or repeal an enacted law. New Mexico became the 47th state on Jan. 6, 1912. President Taft issued a statehood proclamation for New Mexico on Jan. 6, 1912.

The Constitution of 1910 is still in effect today. The constitution was amended 182 times—the process to amend the constitution requires a legislatively referred amendment to be approved by voters, or voters ratifying amendments proposed by a constitutional convention. The last time the constitution was amended was in 2024, when voters approved four constitutional amendments.