The Trafalgar results were especially surprising, because they showed a ten-point jump for Dolan and only a three-point jump for Vance since right before Donald Trump endorsed Vance on April 15, when Trafalgar last polled the race. (They also showed Mandel falling seven points over the same period.)

“Saturday and Sunday, there was a big Dolan surge,” says Robert Cahaly, the pollster who runs Trafalgar. “The snapshot of Sunday doesn’t look anything like the snapshot of Friday. . . . Vance has always been first, but Vance’s lead shrunk and second place switched hands” between Mandel and Dolan. “It wasn’t that Vance was going down. It was just that undecideds were breaking [to Dolan] and making the gap tighter.”

Another positive sign for Dolan in the Trafalgar poll: Among the 9 percent of likely voters in the primary who were still undecided, a solid majority are backing incumbent governor Mike DeWine, a traditional Republican with a profile similar to Dolan’s, in the gubernatorial race: According to Cahaly, in the Senate primary DeWine voters break 33 percent for Dolan, 21 percent for Vance, and 18 percent for Mandel. (Trafalgar finds DeWine at 47 percent in his own primary race, 20 points ahead of his nearest challenger.)