The day after accepting her party's nomination for president in Philadelphia, Clinton boarded a bus emblazoned with her campaign slogan, "Stronger Together." Her motorcade headed west into the country's former industrial heartland, stopping in blue-collar cities like Pittsburgh and Youngstown, Ohio, with a message aimed at white working-class voters -- the very foundation of Trump's support.
On factory floors and in school gymnasiums, Clinton pitched her economic vision to union members, teachers and assembly line workers, most of whom described themselves as part of the lower and middle classes. She promised huge investments to revive manufacturing and higher wage jobs, and a country where "people still make things."
And she repeatedly issued a sober warning about Trump, calling him reckless, inexperienced and out to get the little guy.
"Donald Trump goes around with that hat on, Make America Great Again. Everything he make, he makes somewhere else besides America. The only thing he makes in America are bankruptcies," Clinton said at a K'NEX factory in Hatfield, Pennsylvania, on Friday, surrounded by injection molding presses, surface grinders that flatten steel and other large machinery.
"We don't resent success in America," she added. "But we do resent people who take advantage of others in order to line their own pockets on the way up."
Epicenter of the campaign
With Election Day less than 100 days away, the region spanning the country's Midwest and Northeast is emerging as the epicenter of the 2016 campaign, with Trump's populist message resonating powerfully with the working class here.
Clinton's support in national polls has come largely from non-white voters, women and people with college degrees, while Trump has depended on a strong following of lower-income whites. If Clinton can substantially undercut Trump's support with that group, and even win over a segment of moderate Republicans turned off by Trump, it could devastate the businessman's prospects.
At campaign stops over the weekend, Democrats and independents described Clinton as steady and competent, with an optimistic vision for the country. They contrasted her message against what they described as Trump's darker and more cynical worldview, with some expressing dismay at his volatility and off-color remarks.
Vickie Helman, a 56-year-old Democrat from Harrisburg, Pennsylvania, waited three hours to get into an event with Clinton and her running mate, Tim Kaine, at the Broadway Street Market in the state's capital. She said the city is still filled with rundown areas and it can be a struggle to find a steady job. Helman was recently laid off and went on unemployment for a year before she found her current job at a community college working in mail services.
"If you hear what Trump says and then you hear what Hillary says, it's like night and day. I don't know how anybody could not see that," Helman said.
A group of men she works with, Helman added, is struggling to make sense of the election: "They're Republican, and they say: 'We don't know what we're going to do.' Trump, they say, is just ridiculous."
Chris Wiseman, an administrator at a private school from Landsdale, Pennsylvania, is an independent who supported President Barack Obama in the past two elections. Attending a Clinton campaign event in nearby Hatfield, Wiseman said he believes there is ample opportunity for Clinton and Kaine to win over moderate Republicans in his own community.
"I have a lot of Republican friends and buddies who aren't going to vote Republican this year. They'll either not vote or they'll vote Hillary," said Wiseman, 43. "It's the same group that refused to vote for (John) McCain when (Sarah) Palin was on the ticket."
Kaine helped Clinton make her pitch on the bus tour. The Virginia senator featured his humble roots in Kansas City, his ironworker father and Catholic upbringing in his introduction to this vital part of the country.
"This is the part of the campaign I really like," Kaine said on the first day of the bus tour. "I mean, the big events are fun, but I don't like wearing a tie that much."
Clinton, too, reminded voters of her personal connection to the region. Her grandfather immigrated to Scranton, Pennsylvania, from England and worked in a factory his whole life, she said. Her father was born in Scranton, and she and her brothers spent many childhood summers and Christmases there.
She described the American values instilled in the workers she was meeting on her bus tour.
"We have the most productive, competitive workers in the world -- we just need to give our people the chance to succeed," she said during a visit to Johnstown Wire Technologies, where every surface inside the production floor appeared to be covered with a thin film of white-gray powder. "We're talking to people, meeting people who have each other's backs. And you truly are the reason why I have so much confidence that America's best days are still ahead of us."
While his Democratic opponents were driving through the Rust Belt to sell their economic message this weekend, Trump had become embroiled in yet another controversy.
He went after Khizr Khan, the father of a Muslim-American soldier who died in Iraq, and suggested that Khan's wife had not spoken at the Democratic convention because "maybe she wasn't allowed to have anything to say."
"If you cannot show empathy for a Gold Star mom and dad, there is something fundamentally missing in your personality," Kaine told reporters Sunday morning en route to Columbus, Ohio.
Highlighting Trump's erratic behavior and demagogic rhetoric could pay off for Clinton and Kaine.
When they arrived at East High School in Youngstown on Saturday night, more than two hours behind schedule for their for their last stop of the day, one man stood on the risers behind the stage holding up a red sign that read: "Republican for Hillary."
Sean Cornelius, a 32-year-old worker at an automotive assembly, told CNN after the event that he voted for Trump during the primary.
"There are some things I disagreed on, but he seemed like he was the man," Cornelius said.
But Cornelius, who said he makes a decent living for the area, has been particularly impressed by Clinton's promise to invest billions into manufacturing. And it became impossible for him to continue supporting Trump recently, he said, when the New York real estate mogul appeared to encourage Russia to hack Clinton's emails.
Trump later said he was being sarcastic.
"It doesn't matter if he was being sarcastic or not, you just don't make those type of comments when you're running for public office. And that's what made me decide to go for Hillary," Cornelius said. "Lately, anything just sets him off pretty quick. ...I just don't trust him with the presidency anymore."