The “narrative” coming out of CNN’s Republican debate last week has been that Carly Fiorina notched another victory, in part by crushing Donald Trump. Here at FiveThirtyEight, we take a lot of shots at political media narratives, so it seems only fair to point out that, in this case, the narrative is right: Eight national polls of GOP voters have been conducted related to the Republican race for president since the debate, and they show a couple of clear winners and losers — Fiorina won; Trump lost.
Before we get to that, though, let’s be clear that we’re still talking about polling several months before any voting takes place; a lot can — and will — happen before the Republican nomination is wrapped up. And just as we said after the Fox News debate, it’s better to look at the aggregate of polls (that’s why I waited more than a week to write this). Finally, to control for house effects — a pollster’s tendency to find results that favor one candidate or another — I’m comparing post-debate surveys to the most recent pre-debate poll by the same pollster (i.e., Quinnipiac to Quinnipiac), as long as the “before” poll was conducted within a month of the Sept. 16 debate.