On Monday night, the Democratic National Convention featured speeches from a string of labor leaders. They spoke for different constituencies — teachers, public sector workers, builders — but together they delivered their unifying message: Clinton, not Trump, is the best candidate for American workers.

"He thinks he's a tough guy. Well, Donald, I worked in the mines with tough guys," said Richard Trumka, president of the AFL-CIO. "I know tough guys. They're friends of mine. And Donald, you're no tough guy; you're a phony."

Speaker after speaker blasted Trump on behalf of workers. Democratic Sen. Jeff Merkley of Oregon summed up the message by depicting Trump as predatory: "He is no more a champion for American workers than a lion is a champion for a gazelle."

Onetime rival Bernie Sanders also pumped up Clinton's record with workers. "Hillary Clinton understands that if someone in America works 40 hours a week, that person should not be living in poverty. She understands that we must raise the minimum wage to a living wage. And she is determined to create millions of new jobs," he said.

Trump is particularly strong among the white, blue-collar subset of workers, and his opponents know it.

"He starts from a baseline of support among white working-class voters particularly. That is an important thing that we have to recognize," said Matt Morrison, deputy director of Working America, an AFL-CIO-affiliated group that does outreach among workers who are not union-represented.

The Democrats' appeals countered a Republican convention that painted Donald Trump as a champion of the working class. In his acceptance speech, Trump talked about reaching out to laid-off workers and saving jobs by negotiating trade deals. Silicon Valley entrepreneur Peter Thiel referred to Trump as a "blue-collar billionaire."

And Donald Trump Jr.'s remarks described a real estate mogul with a down-to-earth sensibility, seeing potential in workers whose resumes "don't include the names of fancy colleges and degrees." He later said that he and his siblings "didn't learn from M.B.A.'s; we learned from people who had doctorates in common sense."

Those appeals may have helped deliver Trump's post-RNC polling bounce. Trump made huge gains among white voters without a college degree after the RNC. Before that, he had led among that group by 20 points, according to CNN polling. Now, he leads by 39 points.

During the Republican convention, Trump also tried to extend his message beyond his white-working-class base, for example by mentioning unemployment figures for African-Americans and Latinos.

To gain more workers' favor, Morrison said, Democrats will this week have to convince disaffected voters that government can still solve problems.

"I think at this point, folks have just heard it all, seen it all," Morrison added. "Voters are fed up and feeling like the system isn't connecting to their real-life needs."

Of course, with an opponent who has such high unfavorables (with Clinton close behind), going on the attack can't hurt.

While Trump runs on his business record, groups supporting Clinton are weaponizing it. Monday night, AFSCME President Lee Saunders invoked a dispute in Las Vegas where Trump managers fought food and drink service workers' attempts to unionize.

"Donald Trump wants to tear working people down. He's only in business for himself," Saunders said.

It's nothing new for the economy to be a major campaign topic. However, speaking to Americans' frustrations on a personal level perhaps takes on extra importance as many voters hear about a recovering economy but don't feel many of its effects.

And so November is shaping up to be a battle over which party convinces voters that it can help struggling workers struggle a little less.

At a Monday RNC news conference, former Pennsylvania senator (and former Trump nomination rival) Rick Santorum predicted that some Democrats would defect to support Trump, as he cares about "average workers in America."

"That used to be the Democratic Party. That used to be their message," he said.

One union representative, meanwhile, cast that messaging as deceptive.

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