The race to the White House made a stop in Boston on Wednesday.
Democratic vice presidential nominee Tim Walz spoke at the International Association of Firefighters Convention. This is one of the largest labor unions in the country.
"We know exactly who built this country. It's people like the folks in this room: firefighters, police officers, construction trades, teachers and nurses and veterans," he said. "It was you who built the middle class, and we know when unions are strong, America is strong."
Walz's visit comes a day before he and presidential nominee Kamala Harris will sit down together for their first interview in Georgia during their bus tour of the critical swing state.
Republicans have criticized Harris for her lack of formal interviews.
Meanwhile, Harris and former President Donald Trump are getting ready for next month's debate. where the Harris campaign is pushing for mics to be unmuted the entire time.
"We want that opportunity for the American people to see Donald Trump for who he is, not censored, not muted, but the unfettered guy he is going to be if he becomes president again," Ian Sams, Harris-Walz senior campaign advisor.
As for the Trump campaign, both he and his running mate, JD Vance, are making swings through the key battleground states of Michigan, Wisconsin and Pennsylvania this week.
Vance stopped at a farm in Michigan focusing on the economy and linking Harris to current economic conditions under President Joe Biden.
"We've got to remind her she's the vice president right now. stop talking about what you're going to do. Stop start talking about what you are going to do right now because you're the vice president," said Vance.
Back in Boston, Walz, a former union member himself, told the firefighters' union at the Boston Convention and Exhibition Center that "we see your noble courage. We're forever grateful to you for going above and beyond to keep all of us safe, and we're committed to building a future that you and your families deserve."