[1/2] Caucus goers wait in the corner for Democratic 2020 U.S. presidential candidate and former U.S. Vice President Joe Biden at their caucus site in Des Moines, Iowa, U.S., February 3, 2020.
After Iowa, both Democrats and Republicans hold state primaries that narrow down presidential candidates even further.
Their push to change the primary calendar picked up momentum after 2020 when the Democrats' Iowa caucuses were plagued by technical and communication issues that delayed the announcement of a winner.
The state has traditionally held the first primary, right after Iowa's caucuses, but some Democrats would like more-diverse Nevada to get that spot.
But New Hampshire state law requires its secretary of state to set the primary date seven days before any other, providing state officials a firewall against any efforts to boot them as the first primary state.