Late movement toward Haley in the polls didn’t show up in the caucuses
According to the most recent Iowa polls, Haley was surging in the state, taking second place over DeSantis as of January 11, and increasing her lead over him since then. However, it doesn't appear that this surge in the polls showed up in the actual caucuses, as ABC News has now projected Ron DeSantis to finish in second place. As we wrote in 2016 and 2020, Iowa can be a difficult state to poll because the nature of the caucuses lends itself to voters making strategic decisions that may not be captured in the polls. Unless the race is essentially between two candidates, Iowa polls have historically been all over the map in terms of their accuracy. The fact that the polls got so close this time is, historically, unusual.
—Mary Radcliffe, 538