Though it remains impossible to count out Donald Trump, who still leads the Republican field of presidential hopefuls, an endless barrage of offensive statements may have dented his iron-clad support. A new Reuters/Ipsos poll finds that enthusiasm for the candidate fell by 12 percentage points in less than a week—the single largest drop since he began leading the pack in July.

According to the poll, Trump has the support of 31 percent of Republican voters. The week prior, he was polling at 42 percent.

Trump has had a banner run in the past few weeks. While Parisians mourned the deaths of scores of innocent civilians gunned down in a series of attacks on the French capitol, Trump said he wouldn’t rule out requiring U.S. Muslims to register in a special database, and said French people would have stood a better chance against the terrorists if they all carried guns.

Then, during a Tuesday speech in South Carolina, Trump mocked a New York Times reporter with physical disability. “Now the poor guy, you ought to see this guy,” Trump said, while jerkily moving his arms. “‘Ah, I don’t know what I said! I don’t remember!’” Rebuke came swiftly, and Trump claimed that he had no idea what the reporter, Serge Kovaleski, looked like—an assertion Kovaleski himself disputed, noting that he had covered Trump for decades.

Trump’s invocation of Kovaleski was flawed from the start: the billionaire was trying to defend his claim that he saw “thousands” of Muslims celebrating in New Jersey as the Twin Towers fell on September 11, 2001. (Kovaleski cited in an article after the attacks that unconfirmed reports of “a number of people were allegedly seen celebrating”—reports that Kovaleski this week pointed out were never authenticated by authorities.)

Dr. Ben Carson, hammered by a week in which foreign policy came to the forefront of the American political imagination, also saw his numbers dip to 15 percent. Marco Rubio and Ted Cruz are tied for third place at just over 8 percent a piece, and Jeb Bush is in fourth place, with the support of 7 percent of Republican voters.

Will Trump’s star continue to fade? It’s hard to say: just a week ago, he was riding an ever-rising wave of support that he built while insulting Mexican immigrants, Fox News anchor Megyn Kelly, the entire media, Iowa voters, Rubio’s sweat glands, and basically anyone and anything that otherwise got in his way.