Ken Martin probably never thought he would have to fight so hard to hold on to the “L” in the DFL. But as Democrats converge in Philadelphia to nominate Hillary Clinton as their presidential nominee, the chairman of the Democratic-Farmer-Labor Party is concerned about losing working-class labor voters who formed the heart of the Democrats’ coalition for decades but are now up for grabs.

“Their wages have stagnated, they’re working harder than they ever have, and they’re not getting ahead,” said Martin, who began work in politics in the carpenters union. “Donald Trump is appealing to a big segment of those working people who are frustrated. It creates some issues for us in Minnesota and around the country.”

Many polls and the state’s 44-year unbroken streak of voting for Democratic presidential candidates strongly indicate that Minnesota is out of reach for the GOP nominee, especially given a large population of the college-educated voters Trump has alienated. But if he were to win Midwestern battleground states of Ohio, Michigan, Wisconsin and Pennsylvania, he would almost be assured of the presidency.

All of those Rust Belt states are heavy with working-class voters, many of them economically displaced after a decline in manufacturing and labor unions. Trump’s strategy is to turn them into Republican strongholds by attacking Democrats for accepting free trade deals he asserts have cost jobs and wages, while also appealing to white voters’ animosities toward immigrants and other minority groups.

“He is making an explicit appeal that is all about dividing workers from each other, and we need to expose that” said Javier Morillo-Alicea, president of the SEIU Local 26, comprising 6,000 janitors, security guards and window washers.

Clinton shows strength with teachers and nurses, as well as service employee unions like Morillo-Alicea’s that are on the cutting edge of new tactics and tend to be more racially and ethnically diverse.

So far, Trump may be making headway. Following his nomination last week in Cleveland, he has surged ahead in some forecasts, including in Ohio, Pennsylvania and Wisconsin, where those working-class voters are turning to the outsider mogul as a salve to their years of economic struggle.

“I am concerned,” Martin said. “You don’t have to look any farther than the Eighth Congressional District, the Iron Range and some economically depressed areas of our state, where the economy is lagging behind, and those people feel left behind,” he said, citing Rep. Rick Nolan’s district in northeast Minnesota, where steelworkers have been pummeled by layoffs they blame on the dumping of cheap foreign steel. Nolan is facing a tough re-election challenge by Mills Fleet Farm heir Stewart Mills, who is hammering his rival on the tough Iron Range economy.

Sandra Sandoval, who is a Clinton delegate from Savage, is a retired member, organizer and elected officer with the Communications Workers of America.

“It’s in my blood, you know?”

Sandoval said labor will stand with Clinton, as it has for the DFL since the beginning: “We have made the DFL what it is today. Really we made the country what it is today, and with a Hillary Clinton administration we’re going to be able to keep building on that.”

Highlighting the importance of the labor vote, Clinton and her running mate, Sen. Tim Kaine of Virginia, will campaign throughout Pennsylvania and Ohio on a bus tour starting Friday, the day after she accepts the nomination.

The first night of their convention here was filled with populist appeals from Vermont Sen. Bernie Sanders, who fought Clinton to the bitter end of the Democratic nominating contest by highlighting economic inequality and stagnating wages, his decades long friendship with organized labor and opposition to free trade deals.

“You have heard me say a million times that this campaign is not just about electing a president, as important as that is,” Sanders said at a rally earlier in the day. “It is building a movement to transform this country. Election Days come and go, but the fight for social, economic, racial and environmental justice continues.”

Sanders was introduced at the Wells Fargo Center in downtown Philadelphia by Minnesota Rep. Keith Ellison, an early Sanders backer and key player in his campaign.

“Trump wants to divide and conquer us with his anti-Muslim, anti-Mexican, anti-worker message,” said Ellison, according to an early draft of the speech. When they bring fear, we bring courage. And when they bring division, we bring unity!”

Ultimately, Clinton, who once sat on the board of union foe Wal-Mart, will have to close the sale with many Midwestern labor voters. Many feel burned by the two political figures closest to Clinton: President Obama has negotiated the Trans-Pacific Partnership, which is currently stalled in Congress. And Bill Clinton signed NAFTA, which created a free-trade zone with Mexico and Canada.

Hillary Clinton finally came out against the Pacific trade deal, but only after what some union members perceived as a period of wobbly dithering.

Labor representatives in the Minnesota delegation are bullish on Clinton’s ability to knit together a labor coalition that will carry the Midwest.

Morillo-Alicea is confident that members of the old-line industrial unions will ignore Trump’s racial appeals and come around once members know more about Trump’s foreign-made products and allegations that he has mistreated workers. He compared Trump to Mitt Romney, the vanquished GOP nominee of 2012, whom the Obama campaign portrayed as an out-of-touch plutocrat who was no friend of workers.

“We have seen what a coalition looks like that can defeat him,” Morillo-Alicea said. “We’ve done it the past two elections.” 651-925-5042