Labor Day in Pittsburgh

Joe Biden

Former Vice President Joe Biden drew contrasts with President Donald Trump in style and on substance during a series of Labor Day appearances here on Monday, even as he continued to dodge questions about his 2020 plans.

"We're in a fight for the soul of America," Biden said from the steps of a Catholic church following morning services, as he prepared to march with workers in one of the largest Labor Day parades in the country. 

"Everything" is at stake in the coming midterm elections, Biden added.

Biden's appearance Monday marked his third stop at the parade in four years, and Democratic Sen. Bob Casey, whose re-election campaign Biden sought to boost with his visit, said he has become "a familiar face" at the event.

But the timing of Biden's appearance raised further suspicions about his plans as he mulls another presidential bid in 2020, a process that has seen the 75-year-old raise his public profile at political events in recent months. 

As he marched and mingled Monday, union members urged him to run, with Biden grinning noncommittally in response. 

He literally did run, however -- down the street through crowds of people, with some cheering him on -- in order to catch up to his assigned position in the parade after greeting onlookers, prompting numerous puns on social media.

The former Vice President insisted his decision to march in the parade "doesn't mean anything for my political future."

"I've been with these guys my whole life," Biden said of the workers who walked with him, some pressing him for handshakes and selfies. 

"These are the guys that brung me to the dance, as the saying goes."

Biden did take an opportunity to criticize Trump on trade policy, however, an issue that was at the crux of Trump's pitch to blue collar voters in the 2016 election and has become a flashpoint in his presidency.

Asked whether he would renegotiate NAFTA, Biden drew a contrast with Trump's adversarial approach toward Canada and Mexico in hashing out a new deal, with tensions rising in recent days.

"No, we always can renegotiate everything we have to make it better, but not the way (Trump) is going about this," Biden said. 

Asked to explain where he differs from the President on trade policy, Biden laughed, adding, "You don't have enough time."

Trump has said it would be "a dream" to take on Biden, who has previously sought the presidency without success.

"I'd love to have it be Biden," Trump told CBS News earlier this summer.

Although Pennsylvania swung for Trump in 2016, Pittsburgh was solidly in Hillary Clinton's column, and for Biden, a proud son of Scranton, the city felt like home turf Monday. 

The message he brought to the home crowd sounded at times like a budding stump speech for the Trump era.

At a picnic for electrical workers -- where Biden shared a stage with Conor Lamb, who won a narrow victory in the special election for Pennsylvania's 18th Congressional District -- the former Vice President spoke of his optimism for the country.