New York Times | By KATHARINE Q. SEELY FEB. 7, 2016
HANOVER, N.H. — Hillary Clinton’s campaign maintains that Senator Bernie Sanders could win New Hampshire’s primary on Tuesday because he comes from neighboring Vermont. As Bill Clinton told NBC News: “Nobody from a state bordering New Hampshire has ever lost a Democratic primary to a non-incumbent president.”

A hockey game on Saturday in Cabot, Vt. Though Mr. Sanders is from Vermont, that may not give him an advantage Tuesday in the primary in New Hampshire, which leans libertarian.  Credit: Christopher Capozziello for The New York Times

But as natives of New Hampshire and Vermont are quick to note, if Mr. Sanders wins New Hampshire, it may be in spite of his coming from Vermont, not because of it.

From afar, Vermont and New Hampshire look like two peas in a pod. But from the Birkenstock outlets in Vermont to the Harley-Davidson dealerships in New Hampshire, these two states, on opposite sides of the Connecticut River, could not be more different.

They sprang from different geological forces that produced the soft rolling Green Mountains of Vermont and the rugged, angular White Mountains of New Hampshire. The differences run through their colonial histories and are evident today in their cultures, politics and certainly in their state mottos: Vermont’s feel-good “Freedom and Unity” shrinks before New Hampshire’s stark ultimatum to “Live Free or Die.”

Supporters of Senator Bernie Sanders on Sunday in Northwood, N.H. Credit: Christopher Capozziello for The New York Times

“Those mottos tell you everything you need to know,” said David Briggs, a civil engineer and lifelong Vermonter, who owns the Hotel Coolidge in White River Junction, Vt. “Ours is about individualism, but the ‘Unity’ reminds us we’re interdependent. Now, ‘Live Free or Die’ — that’s almost jihadist.”

While the Vermont electorate is liberal and its ethos collectivist, the New Hampshire ethos is fiercely libertarian. New Hampshire is the only state that does not ticket adults if they are not wearing a seatbelt.

“The essential difference between Vermont and New Hampshire is in their degree of commitment to state authority,” said Jere R. Daniell, a retired historian from Dartmouth College, here in Hanover. This manifested itself some years ago in the phone book, he said, when listings for the Vermont state government took up 62 inches, while New Hampshire’s took up eight.

Comparing and contrasting these two states has been a parlor game in New England for decades, if not centuries. It has produced academic studies and irreverent analyses, like one that boiled down the differences to this: “Basically, if you live in New England and want to join a militia, then New Hampshire is for you. But if you want to skip showering and listen to NPR, then head on up to Vermont.”

“Its default mode is grumpy,” Willem Lange, a New England storyteller, said of New Hampshire. Credit: Christopher Capozziello for The New York Times

“There are so damn many liberals,” he added, “I can never win an argument.”

Mr. Lange said he missed the bracing honesty in New Hampshire, where, he said, people would read his column and tell him that he was an idiot. “In Vermont they just say, ‘Oh, that was a lovely piece,’ ” he said.

Vermont was once the most Republican state in the country and is now among the most liberal, thanks in part to an influx starting in the 1960s that included people like Mr. Sanders, although local politics had already started trending Democratic.

While many places around the country took on a “loose” hippie cast in the late ’60s, “Vermont seems unique in the degree to which an entire state was, and still is, seen through this lens,” wrote Jason Kaufman and Matthew E. Kaliner of Harvard in a 2011 study of the two states.

As Vermont’s reputation changed, more counterculture migrants moved in and reinforced the state’s crunchy, artistic and socially conscious stereotype, the authors wrote. They said Vermont had twice as many Birkenstock dealers per capita as New Hampshire, more vegetarian restaurants and more hemp product dealers.

New Hampshire’s migrants were more likely to be economic refugees, especially from Massachusetts (“Taxachusetts”). Most of the state’s population is in the suburbs along the southern tier.

“When I cross the river into Vermont, I can see the difference and feel the difference,” said Rebecca Rule, a New Hampshire humorist and storyteller. “The fields open up, it’s more rural, there are more farms and more cows. Vermont is a gentler place. New Hampshire is more hard-edged.”

She also sees more stickers and peace signs on cars in Vermont. “You don’t see that as much in New Hampshire,” she said. “Most of us would just as soon not have anybody know how we feel.”

New Hampshire has always been more mercantile. At one time, the brick mills in Manchester, running along the Merrimack River for a full mile, were the largest cotton mills in the world.

New Hampshire has no sales tax and no general income tax. Money for schools and other services is raised mostly through property taxes, but services are minimal. The University of New Hampshire is the most expensive public four-year college in the country because the state’s rate of support for higher education is the nation’s lowest.

A version of this article appears in print on February 8, 2016, on page A10 of the New York edition with the headline: More Than a River Separates Sanders’s State From Primary’s .