Nashville singer-songwriter Jason Isbell couldn't make time for an interview with us last week, and that's OK: On Aug. 20, he headlined a rally for Phil Bredesen, former Tennessee governor and current Democratic candidate for Senate.

In the days leading up to and following that performance, Isbell had to deal with the fallout of being labeled part of the "unhinged left" by the National Republican Senatorial Committee—a strange claim for a man who grew up in rural Alabama and leads a very public life as a humble recovering alcoholic. "I was thinking today about how it feels to be an unhinged leftist," Isbell joked from the stage, where he performed after piano-pounding symphonic rocker Ben Folds. "For the first time in my life, I'm hinged. I quit drinking years ago, I got a 3-year-old daughter ... This is as hinged as I get. I'm hinged as hell!"

Isbell is just the kind of outspoken artist-activist a moderate candidate like Bredesen needs on his side. Across six albums—released either solo or with his backing band, The 400 Unit—Isbell has sung with incisive care and astute anger about his blue-collar roots. He mixes songs about domestic bliss—he and his fiddle-playing wife, Amanda Shires, who's built her own acclaimed career, have that aforementioned 3-year-old daughter, Mercy Rose—with searing indictments of a "White Man's World."

He writes lovingly from the perspective of characters who work in mines, get pulled over in speed-trap towns and get blind drunk in the bleachers of high school football games. On 2015's "If It Takes a Lifetime," he begins each verse with the torrid line "I got too far from my raising/ I forgot where I come from." On "Something More than Free," he sings, "And I don't think on why I'm here where it hurts/ But I thank God for the work." On "Outfit," one of the first songs Isbell wrote in 2003 as a part of Southern rock band Drive-By Truckers, he repeated the advice his father, a house painter, gave him as a teenager: "Don't try to change who you are boy/ And don't try to be who you ain't/ And don't let me catch you in Kendale with a bucket of wealthy man's paint."

We could go on and on, but the point is this: Isbell is precisely the kind of songwriter the U.S. needs right now. Yes, he's an active Twitter user whose politics lean in a decidedly progressive direction. But because of his upbringing, his humility and his success, he's the rare artist who can bridge the country's yawning socioeconomic and political divides. He digs into the morals of his stories through character-driven narratives that unfold like the peels of sweet Vidalia onions, not heavy-handed leftist screeds.

In 2015, he told Grantland, "Politics are a very personal thing, and those stories are reflective of a bigger truth. I try to make statements that aren'tbroad because that doesn't make for good writing ... I have to be small, I have to make the stories a bit personal." Pointing out an obvious fact, he added, "The middle class is disappearing—it's all but gone at this point, and it's going to get worse before it gets better."

Isbell continues to move up in the performing world, graduating from bars and clubs to theaters and arenas. Two nights before performing at the Nashville rally for candidate Bredesen, he appeared on the field with The 400 Unit at SunTrust Field in Atlanta, quite a high honor for a diehard Braves fan. And when you take the line that so angered Republicans—"God is gone from those people," Isbell said of Trump voters in a 2017 Rolling Stone interview—and hold it up to the light, it certainly doesn't look quite so unhinged. Consider the way Isbell finished his set at the Bredesen rally, reaching the explosive crescendo of "White Man's World" before coming down in a pique of reflection:

"There's no such thing as someone else's war

Your creature comforts aren't the only things worth fighting for

You're still breathing, it's not too late

We're all carrying one big burden, sharing one fate

I'm a white man living in a white man's nation

I think the man upstairs must have took a vacation

I still have faith, but I don't know why

Maybe it's the fire in my little girl's eyes."

If that honest, Southern voice framed by mainstream Christianity and family values is the soundtrack of today's left, the times should certainly be a-changing come November.