Few election prognosticators believe the Tar Heel State will be a big difference-maker to Clinton’s hopes in November; if she wins there, Clinton likely will have won the presidency comfortably. Taking North Carolina, in other words, is more about running up the score.

Why the switch? Just look at the polls. The Clinton campaign announced the original Obama rally on June 9, but it was probably agreed upon a few days earlier when the president decided to endorse her. In early June, her lead over Trump in the Real Clear Politics average was about two points. Three weeks later, after a damaging month for the presumptive Republican nominee, Clinton’s advantage is more than six points. Clinton’s lead in Wisconsin is more than seven points in the RCP average, while in North Carolina, Trump has a slight advantage.

The campaign still wants to use Obama chiefly as a validator for Clinton who can reach out to Bernie Sanders’s supporters by citing his own past suspicions of her. As White House communications director Jen Psaki told Politico, the president is “the highest-profile convert” in Clinton’s corner. That seemed to be the idea behind sending Obama and Clinton to Wisconsin, a state that Sanders won in the primaries. But she needs the suddenly popular president to excite the Democratic base, whether it is by persuading white liberals in Green Bay or making sure African Americans in Charlotte turn out for her in the same numbers they did twice for him.

Swapping out Wisconsin for North Carolina now doesn’t mean Clinton and Obama won’t return to the Badger State later (together or separately), either because the race tightens again or perhaps to help Democrat Russ Feingold in his bid to win back the Senate seat he lost in 2010. Obama is expected to campaign frequently on Clinton’s behalf later this summer and fall. Yet in contrast to Trump, who has campaigned already in several states that don’t figure to be competitive in November, Clinton has been exceedingly deliberate in her schedule so far. Choosing one state for another to campaign with her most powerful new surrogate for the first time isn’t just about logistics. It reflects a campaign that has swung solidly toward her in the last few weeks.

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