Noah took a detailed look at it here.
There were a few things about the poll that struck me:
• Trump at 43 percent, with 63 percent saying that their minds are made up, puts his floor lower than I expected, at 27 percent. If he were to fall to that level (no guarantee, obviously), he could still win depending on how the rest of the vote is distributed, but it’s not an unbeatable number.
• There are several problems with the breakdown of the DeSantis-Haley vote. One is that they are tied, an ideal scenario for Trump. Two, they are pulling from different pools of voters, which makes it possible they both will continue to show resilience. Three, and relatedly, the collapse of one won’t necessarily help the other as much as one might hope — for instance, 41 percent of DeSantis supporters say that Trump is their second choice.
• Even though DeSantis has steadily slid for months now everywhere and it’s difficult to bounce back after deflating for so long, I think you’d still rather be him. He has the highest favorables in Iowa of anyone and 67 percent of voters are considering him, the same number as are considering Trump. This suggests that while DeSantis has failed to hold his level of support during the campaign — of course, a very important metric — it has successfully defended his overall viability, at least in theory.
That said, there’s no sugar-coating the fact that this is a good poll for Trump, and likely the only way to beat him is for someone to have a category-defying surge based on caucus-goers making a decision for one of the Trump alternatives en masse.