MANCHESTER, N.H.—“I’m running against a fella who lives right south of here,” President Bush told a crowd of supporters on Friday, speaking just 20 miles from the Massachusetts border.

But far from a geography lesson, the president’s off-hand remark, one of five references to his opponent’s home state in the span of 30 minutes, highlighted a not-so-subtle culture war lying in the subtext of this year’s presidential campaign.

In the aftermath of Thursday night’s debate in Coral Gables, Fla., the Bush campaign marched north through Allentown, Pa.—stopping to assail “the senator from Massachusetts”—before arriving in Manchester, where the president repeatedly invoked the Commonwealth as though it were a founding member of the axis of evil.

Referencing Sen. John F. Kerry’s notorious line, “I actually voted for the $87 billion before I voted against it,” the president appealed to his seemingly plain-speaking supporters in the Granite State.

“Not a lot of people in New Hampshire talk that way,” Bush said.

Having supported the president by a slim margin in 2000, New Hampshire, with its four electoral votes, has once again emerged as a contested state in this year’s election, attracting the concerted efforts of both major campaigns.

Forty-six Harvard undergraduates made the short trip to Manchester on Friday, cheering on their president at an afternoon rally in a secluded ski resort on the outside of town.

They were like a large portion of the audience who, judging by the license plates in the parking lot, crossed the Massachusetts border to attend the event.

The out-of-town crowd and proximity to Massachusetts placed Bush’s Bay State-bashing in an unusually awkward context, although the president’s audience hardly seemed to mind.

Citing his own campaign’s figures, the president repeated his claim that Kerry had proposed an extraordinary $2.2 trillion in new programs over the course of his campaign.

“And that’s a lot,” Bush said, invoking a favorite line from his stump speech, “even for a senator from Massachusetts.”

The crowd laughed and cheered.

But Kerry’s campaign disputes that figure, and Massachusetts’ reputation as free-spending and high-taxing is at least two decades out of date.

The Bay State ranks 47th in the nation for tax burden imposed on its residents in 2002, according to a study by the Massachusetts Taxpayers Foundation, falling well below Texas, the president’s home state.

Still, the Bush campaign has found success in playing on traditional stereotypes of Massachusetts, even in the state’s own backyard.