Democratic presidential nominee Hillary Clinton, left, accompanied by her running mate Tim Kaine, former president Bill Clinton and Kaine's wife, Anne Holton, gives a thumbs up as she takes the podium to speak at a rally at Temple University in Philadelphia on July 29. (Andrew Harnik/AP)

PHILADELPHIA — Democratic presidential nominee Hillary Clinton and her running mate Sen. Tim Kaine campaigned in Philadelphia on Friday, kicking off a three-day bus tour to cap their party’s national convention.

“We’ve had a great convention but now we’ve got to go out and fight for our vision of America,” Clinton told the crowd at Temple University.

The running mates were joined by their spouses, former president Bill Clinton and Anne Holton, both of whom looked on from their perches on the stage.

Hours after Clinton officially became the first woman to become a major party’s nominee, she said that after her excitement from the night wore off, she was struck by the gravity of the campaign.

“It was also kind of overwhelming,” Clinton said. “I take deeply and with great humility the responsibility that this campaign imposes on us.”

The two parties' conventions could not have been more different, Clinton added.

“We might as well have been talking about two different countries … or two different planets,” she said, noting that the Republican convention in Cleveland last week painted a “negative, dark picture of a country in decline.”

“I’m not satisfied with the status quo. I’m not telling you everything is peachy keen,” Clinton said. “We’ve made progress, but we have work to do if we’re to make sure everybody is included.”

The bus tour will take the pair to Pennsylvania and Ohio, two states that are critical battlegrounds in the November election.

“This is the part of the campaign that I really like,” said Kaine, of Virginia. “I don’t like wearing a tie that much. I’d rather go out and pound the pavement.”

They will focus on the economic concerns of working-class voters in the rustbelt, a key group that may lean toward Republican nominee Donald Trump.

According to a Clinton aide, as they kick off their tour in Hatfield, Pa., later in the day, they will visit a toy manufacturing facility to promote Clinton’s policies for STEM jobs.

Clinton pledged that in her first 100 days she would "break through the gridlock in Washington" to push an economic plan that would be the biggest investment in new jobs since World War II.

The plan would focus on infrastructure, technology, clean energy, and advanced manufacturing jobs, Clinton said.

"I'm also going to pay special attention to those parts of our country that have been left out and left behind," she said.

Phillip reported from Washington.