DAVID GREENE, HOST:
Across the country, dozens of counties voted for President Barack Obama and then voted for President Trump in 2016. In Iowa, where there's a Democratic debate tonight, almost a third of the state's counties flipped from Obama to Trump. The results in Iowa represent an important political shift in our country. And NPR's Asma Khalid visited the county in Iowa with the most extreme swing. And she gives us this snapshot.
ASMA KHALID, BYLINE: Back in 2016, Laura Hubka could feel her county converting as she campaigned for Hillary Clinton.
LAURA HUBKA: People were chasing me out the door, slamming the door in my face, calling Hillary names.
KHALID: Hubka is the chair of the Democratic Party in Howard County. It's a tiny place on the Minnesota border that's mostly white, rural and religious. It had a 41-point swing from Barack Obama to Donald Trump. Talk to people here, and they'll give you a couple of possible explanations for that massive shift. Some point to white, working-class union voters who bought into Trump's economic promises. Others point to the moment the local theater showed a movie that smeared Hillary Clinton. Whatever the reason, local Democrats want to make sure they can win back some voters. But they're torn on how to do that.
HUBKA: Republicans stand behind their candidate. Like, the Democrats have to fall in love. We have to be, like, oh, Barack Obama. You know, I don't feel like people are, like, oh, Joe Biden, you know - and that's a problem.
KHALID: Hubka is not supporting the former vice president. Instead, she's backing the former mayor of South Bend, Ind., Pete Buttigieg. So is Dale Ernst (ph).
DALE ERNST: I'm the precinct captain for Pete. I think he's just kind of a calm voice in the middle of the chaos, which is what we're in the middle of now.
KHALID: I met Ernst recently, along with some 20 other Democrats, at the local chamber of commerce, which also happens to house the Iowa Wrestling Hall of Fame. Random fact - this tiny county is home to multiple Olympic wrestlers. Ernst, like some other folks here, is looking for a moderate candidate. And he's worried about some ideas on the left of his party. The 66-year-old is skeptical of "Medicare for All."
ERNST: I just don't think it's reasonable. I just really don't. I think for people younger than 65, they see this more free than, really, the cost of it.
KHALID: Another voter here, Sally Godwin, thinks Buttigieg is too young. And she would love to see a woman, though she thinks Massachusetts Senator Elizabeth Warren is too old.
SALLY GODWIN: Amy Klobuchar is kind of right in the middle. I like what she has to say.
CONNIE HVITVED: She is. She is right in the middle.
KHALID: That's her friend Connie Hvitved you heard there at the end. She's also leaning toward the Minnesota senator. Democrats, regardless of who they're supporting, insist that people are more involved this presidential election. But they're still not confident. Here's Laura Hubka, the Democratic Party chair, again.
HUBKA: I will do my best to try to get this county back. I don't have high hopes that it'll - I don't know in November that it'll flip completely. I hope that I can get at least 10 of points folks back or, you know, 15.
KHALID: Local Democrats like Dale Ernst say the best way to ensure the county flips back is for national Democrats to pay attention to places like his.
ERNST: Coming to a place like here, where the swing was 20 to 20, I think it steers the ship. It gives a good idea of where we should go.
KHALID: Democrats can turn to history for some hope. The last time the county went for a Republican prior to Donald Trump was 1984 for Ronald Reagan. Four years later, it turned blue again.
Asma Khalid, NPR News. Transcript provided by NPR, Copyright NPR.