In the past, there were up to 15 states that held Presidential Caucuses, with them first evolving in the 1970s.
Today, in 2024, there are only a few states that hold caucuses, with the overwhelming majority having Presidential primaries.
The only states in 2024 with caucuses being held by both major political parties are:
Hawaii
Idaho
Iowa
North Dakota
Wyoming
Two other states have Republicans having caucuses, while Democrats have primaries
Those two states with this odd situation are
Missouri
Nevada
Notice none of these total seven states have large populations, with Missouri being the largest.
At the same time, the Iowa Caucuses have NOT been a good example of accuracy as to who would be the nominees or winners of the Presidency.
The only Presidents who won in Iowa and went on to the White House were:
Jimmy Carter 1976
George W. Bush 2000
Barack Obama 2008
Walter Mondale in 1984, Al Gore in 2000, John Kerry in 2004, and Hillary Clinton in 2016 won the Iowa Caucuses but lost the Presidency for Democrats, while for the Republicans, only Bob Dole in 1996 won in Iowa and then lost the Presidency.