On Wednesday, Suffolk University published a poll showing Donald Trump ahead of John Kasich, 68 percent to 23 percent. That’s not a great number for Kasich, who has been considering a primary challenge against Trump in 2020. But does a poll this early in the cycle mean anything?
Obviously, primary polls taken this early get a lot wrong. In open primaries, early national polls sometimes even get the field pretty wrong—half of the candidates they poll don’t run and they leave out about half of the candidates who do end up running. Rewind just four years for a good example: In Suffolk’s June 2014 poll of New Hampshire, Chris Christie led a pack that didn’t include Trump or Kasich (the first and second place finisher) and early polls of the 2016 Democratic race didn’t include Bernie Sanders.
But those examples come from open primaries. Primaries that feature an incumbent are easier to predict (because the incumbent usually wins). And these numbers may capture a more Kasich-specific problem: In 2016, Kasich ran as an essentially factional candidate, scoring some of his biggest victories in areas with numerous well-educated, moderate Republicans. That’s a real part of the party, but it’s simply not enough to win a Republican nomination. Kasich got 16 percent of the Republican vote in New Hampshire in 2016, but only ended up winning one state the rest of the way (his home state of Ohio). Suffolk’s new 23 percent figure is a little higher than he finished in New Hampshire last time, but it doesn’t signal the sort of strength necessary to beat an incumbent in a long primary that runs through a wide variety of states.
Trump is also an incumbent with a high (albeit lukewarm) approval rating among Republicans. Some of those voters might be persuaded to vote against Trump in a Republican Primary—both Gerald Ford and Jimmy Carter had low approval ratings and faced tough primary challenges when they ran for a second term. But it’s not clear that all these lukewarm voters would prefer a factional candidate like Kasich to Trump. Put differently, Trump may end up facing a serious primary challenger, but it’s not clear that Kasich has the range within the GOP to be that guy.
The more interesting question for Kasich (and one that I didn’t see in this poll) is how he fares as a third party candidate. Third party candidates tend to have a tough time winning. But if Democrats nominate someone from the left side of the party (e.g. Elizabeth Warren, who actually leads the Democratic field in the Suffolk poll) and Trump has taken more damage heading into 2020, it’s possible to imagine some voters opting for an independent candidate (as many did in 2016) and allowing Kasich outperform previous third-party candidates.

