More than 160,000 people registered to vote in the space of 48 hours after Taylor Swift finally weighed in on American politics this week, sparking excitement on the left that the country-cum-pop star could even seal a Senate seat in Tennessee.

Swift declared her support for two Democratic candidates in a post on her Instagram account on Sunday. Less than five weeks ahead of the November midterm elections, which are widely seen as a referendum on Donald Trump’s America, Swift’s intervention has prompted a mixture of praise, chin-stroking and outrage.

The 28-year-old is far from the first celebrity to express her political views, but her young fans – she has more than 112 million followers on Instagram – are seen as particularly loyal and impressionable.

But will the Swift intervention make a difference?

“One hundred percent,” said Tee Cahours, who was tending bar at Crazy Town in Nashville’s touristy Broadway strip. “She’s a huge icon not only in pop but country music – she’s the reason that nowadays people are more likely to listen to country.

“Purely because of that reason her fans will say: ‘Oh, Taylor Swift likes this person, I’ll trust them.’”

Crazy Town is one of about a dozen almost indistinguishable – live band, happy hour discount on Miller Lite, faint but distinct smell of vomit – establishments that line Broadway in downtown Nashville. The crowd is mostly grey-haired, and frequently inebriated, but at 20 years old, Cahours is in the age bracket of people who might be seen as susceptible to Swift’s politics. Cahours said she was not a Swift fan – but she understood her potential influence.

“Right now I really like this artist Russ [a rapper who has cited Eminem as an influence],” Cahours said.

“And if he was to post that he was going to vote for a specific presidential candidate, I would be more likely to vote for who he said he was going to vote for. It’s almost the same thing as children voting for the same person as their parents voted for, and I think it’s the same thing in the music industry.”

According to Vote.org, a non-partisan group that seeks to boost turnout in elections, there was a spike in voter registration after Swift’s post, which mentioned the website. By midday on Tuesday – less than 48 hours after Swift’s post – more than 169,000 new people had registered to vote, Kamari Guthrie, director of communications for Vote.org, told the Washington Post.

By comparison, Vote.org added only 56,669 new voters during the whole of August.

The two Democrats Swift endorsed were Phil Bredesen, who was governor of Tennessee for eight years until 2011 and is hoping to make it to the US Senate, and Jim Cooper, who is running for the House in a district which encompasses Nashville – traditionally a more leftwing dot in the midst of a conservative state.

Some believe that if Swift can make a difference, it will be at the local level.

“She’s from the area,” said Kip Wood, a twentysomething who works as a tour guide in Nashville. “It’s a hometown hero kind of thing. Also, it’s kind of liberal here.”

Wood, who is originally from south Georgia, was drinking light beer in the Red Door Saloon, a mile west of Crazy Town and a stone’s throw from Swift’s penthouse apartment in Nashville’s midtown district.

“But outside of Nashville I have no clue.”

That may be the fly in the ointment for those hoping Swift could help Democrats at a statewide or national level.

Celebrity endorsements, in American politics at least, have been happening for decades. The Rat Pack, including Frank Sinatra, Sammy Davis, Jr and Dean Martin, recorded an alternate version of Sinatra’s hit High Hopes during John F Kennedy’s 1960 presidential campaign, while 40 years earlier Warren G Harding, a Republican, was supported in his successful presidential run by the silent film stars Douglas Fairbanks, Lillian Gish and Pearl White.

But for all the attention the backing of famous people tends to attract, the jury is out on the impact of celebrity political endorsements, on a national level at least. The consensus among political experts seems to be that endorsements are unlikely to change voters’ minds unless they are particular fans of that celebrity.

The standout example is that of Oprah Winfrey endorsing Barack Obama in his 2008 primary race against Hillary Clinton. University of Maryland economists Craig Garthwaite and Tim Moore researched the impact of Winfrey’s backing and believe she was responsible for an additional 1m votes for Obama.

Time will tell whether Swift can wage a similar influence. While Cahours and Wood believe she will summon their peers to the polls, the view from the older crowd, being steadily disgorged outside the Country Music Hall of Fame and Museum on Thursday, was rather different.

“I am a diehard Republican with conservative views,” said Michelle Marks, a 49-year-old from Pennsylvania. Marks was hovering close to the museum’s Taylor Swift Education Center, a series of classrooms where children can attend classes on songwriting and music.

“Most country people are conservative. I think you’re entitled to your opinion but just because you’re a celebrity you don’t need to force your views on me.”

Marks, who said she liked Swift’s country music but was “not a fan of her pop music”, was at the museum with her husband, David Marks. A gruff, mustachioed military veteran, David Marks was celebrating his 57th birthday on Thursday. He said he would not be influenced by Swift’s Democratic tendencies.

Among the museum’s wares is a gold-plated Cadillac that once belonged to Elvis Presley – it has a refrigerator and record player in the back – and outfits and guitars that once belonged to the likes of Hank Williams and Dolly Parton.

Paulette Nordahl, who was in town from northern California for a “girls weekend” with a friend, was looking for the Garth Brooks exhibit, having already peered at items once belonging to her other favorites George Strait, Randy Travis and Helen Jackson.

“You can understand the words,” Nordahl, 67, said of her attraction to country.

“The music – you can actually hear it, and it has a nice rhythm. As long as it’s not twangy.”

Nordahl a retired schoolteacher, said that despite her love of Brooks, Strait et al, she would never vote strictly at their behest.

“I’d still be looking into all of it pretty darn good,” Nordahl said.

“I think everyone should use their own mind, and their own heart, and do what they think, not what someone else thinks,” she said.

In early November, we should get an indication of whether people have followed that advice.