On Dec. 31, 2016, Sam Hunt was already at the top of his game: His multi-platinum, Grammy Awards-nominated debut album, 2014's Montevallo, and its four No. 1, platinum-certified singles, had made Hunt a hot commodity.

And then, he got even hotter thanks to a one-two punch: major relationship news to go along with an unexpected song, followed a few weeks later by a cross-genre smash-hit single called "Body Like a Back Road." You might have heard of it.

Shortly after midnight on New Year's Day, Hunt surprise-released a brand-new track, "Drinkin' Too Much." The song is an apology of sorts to Hannah Lee Fowler, his then-on-again-off-again girlfriend who inspired much of Montevallo's material (and her hometown, its title). At the time, Hunt and Fowler had already gotten back together, though he'd remained mostly quiet about the relationship's rekindling, simply sharing the occasional photo of Fowler on his Instagram account and letting fans put the puzzle pieces together; followers latched on to whatever details they could get their hands on, however, and after someone found a picture of the pair together at Breakout Nashville, in which a ring can be seen on Fowler’s left ring finger, engagement rumors began swirling.

I remember thinking, 'Okay, finally, it feels like it has potential to be something,' but I still had no idea that it would become what it has become.

A rep for Hunt confirmed that the singer and Fowler were engaged one day after the release of "Drinkin' Too Much" (Jan. 2); Hunt and Fowler wed on April 15, just under two weeks after he, during his performance at the 2017 ACM Awards, snuggled up next to Fowler and sang to her on national TV. And while that would have been enough to keep Hunt in the forefront of people's minds, on Feb. 1, Hunt shared a brand-new single, "Body Like a Back Road" -- a light, crazy-catchy, two-and-a-half-minute track that you've definitely heard because it's been everywhere in the six months since its release.

"I wanted to put out a song because we had a tour coming up, and that was a fun song that reflected the spirit of the tour, I thought," Hunt tells The Boot backstage at his recent 15 in a 30 Tour stop in Canandaigua, N.Y., "and so I put it out, but I had no idea that it was going to do what it has done for my career."

Hunt wrote "Body Like a Back Road," following his and Fowler's engagement, with his go-to collaborators, Zach Crowell (also Hunt's producer), Shane McAnally and Josh Osborne. Of the songs he's released, you can count on one hand the number that don't feature at least one of those three men as a co-writer. Clearly, it's a winning team -- and besides, it's hard to replicate those relationships with new people.

"There's something about having been there from the beginning that I can't go back and re-live with a new co-writer," Hunt muses. "There are things that they know about me, that they know about what I wanna do and what I wanna say and how I wanna say it, and they just can't be -- I can't get there with a new co-writer in less than -- how long have I been [doing this]? Four years? -- in less than four years."

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In June, "Body Like a Back Road" broke a 55-year-old record on the Billboard Hot Country Songs chart, making Hunt the solo artist with the longest run at No. 1 on the 59-year-old chart. This week (chart week dated Aug. 5), the song is at the top of the Hot Country Songs, Country Streaming Songs and Country Digital Song Sales charts for its 24th consecutive week, tying Florida Georgia Line's "Cruise" for the Hot Country Songs chart's overall record. In May, "Body Like a Back Road" spent three weeks at No. 1 on Billboard's Country Airplay chart; it's now at No. 6 on that chart, but not before spending a record-breaking 16 weeks in its Top 5.

"I finished singing it and we finished working on the track and the recording of it the night before we put it out," Hunt recalls of creating and releasing "Body Like a Back Road." (Hunt's an admitted perfectionist, so it's not overly surprising that he was still making tweaks as the clock was closing in on metaphorical midnight.) "I listened to it on my ride home from my buddy's house, who lives right down the street, and I remember thinking, 'Okay, finally, it feels like it has potential to be something,' but I still had no idea that it would become what it has become."

In addition to its country chart success, "Body Like a Back Road" is in the Top 30 (No. 21) on the Adult Contemporary chart, the Top 20 (No. 17) on the Pop Songs chart and the Top 10 (No. 9) on the Adult Pop Songs chart. It's also at No. 10 on the all-genre Radio Songs chart and at No. 9 on the all-genre Billboard Hot 100 chart, and the song that Hunt's fans sing the loudest at shows (which is saying something, because, really, they sing everything loudly).

If I have a song that can transcend genre lines and appeal to a pop audience, I'm all for it, but doing different versions of songs, I'm not necessarily into that.

Are you getting the point yet? Hunt has country music's song of the summer -- possibly its song of the year -- and one of 2017's defining songs, period. He's on top of the musical world and, thanks to "Body Like a Back Road," still moving up, even without more new material to share.

"There's been a whole new wave of new fans in the last two or three months, I feel like -- fans that are just picking up [Montevallo] for the first time," Hunt says of the major changes he's seen to a career that was already skyrocketing before "Body Like a Back Road" took off. "So, it's cool to see, at some of the shows, an audience that is mostly fans who have been there from the beginning, but you can tell that there's a large part of the audience [that] are new fans ... and sort of have that enthusiasm that brand-new fans have."

Although it's come his way -- a number of his previous singles have landed on Billboard's non-country and all-genre charts as well -- Hunt hasn't particularly chased success outside of country music. Traditional-leaning country fans may decry his speak-singing style and hip-hop-influenced production, but Hunt isn't about to re-work his material to try to appeal to a wider audience. His label has pitched him on the idea "so many times," he says, asking about adding a rapper to a track or pumping up the bass for a pop-friendly remix, and he's just not interested.

"I'm just not -- I don't like that, you know? I mean, like, why? What's the point?" Hunt muses. "The song is what it is. If people are enjoying it in the pop market, then why would you go and start messing with it?

"If I have a song that can transcend genre lines and appeal to a pop audience, I'm all for it," he adds, "but doing different versions of songs, I'm not necessarily into that."

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