Former US vice president Joe Biden dropped teasing hints Tuesday that he could soon announce a 2020 White House campaign, telling an enthusiastic crowd that he may need their energy "in a few weeks."
The Democratic elder statesman has been mulling a challenge against President Donald Trump for months.
While he tops nearly all early polls for the Democratic nominations race, strategists and election observers have stressed that he is under pressure to enter the crowded field soon, or bow out.
Biden, a consensus-building pragmatist and Washington establishment fixture, is almost certain to jump in, with a campaign kickoff expected by mid-April, sources recently told The New York Times.
Much about Biden's address to the International Association of Fire Fighters in Washington suggested he is in: attendees waving printed "Run Joe Run" placards; recollections from his blue-collar roots; criticism of Trump without naming him; and soaring oratory about America's "creed" and the nation's leadership role in the world.
"I appreciate the energy you showed when I got up here," the 76-year-old told the fire fighters. "Save it a little longer. I may need it in a few weeks."
The room rose in unison for a standing ovation, and Biden laughed as he said "be careful what you wish for."
The event, attended by Biden's wife Jill, could easily have been mistaken for a campaign stop.
The would-be candidate himself jogged on stage to Bruce Springsteen's "We Take Care of Our Own," followed by firefighters chanting "Run, Joe, run." Biden quoted from the Declaration of Independence.
He would be an instant frontrunner should he enter the race, occupying the centrist lane in a field of Democrats whose party has steadily shifted leftward in recent years.
Senator Bernie Sanders currently leads the liberal charge of 2020 candidates.
Biden has another noteworthy speech this week. He addresses a Democratic Party dinner Saturday in Delaware, the small state he represented for 36 years in the US Senate until his stint as Barack Obama's deputy.
Fellow Delawarean Chris Coons, who replaced Biden in the Senate and speaks with him regularly, said all signs point to Biden jumping in.
"He is moving closer, he's someone who I am confident is going to run," Coons told CBS on Monday.
"Everything is being put in place but that last decision, which you know understandably is a big decision."
Biden clearly spoke in the inspirational timber of a candidate, insisting that what makes America great is " giving everyone a fair shot, leaving no one behind, demonizing no one."
"We're not able to be defined by race, by religion, by tribe," Biden said.
"That's what the next president of the United States needs to understand, and that's what I don't think this current president understands at all."
He hit out at the tone of the Trump era, saying extremism is on the rise and "mean pettiness has overtaken our politics."
And he took aim at the current administration's policies, including the Republican "tax cut for the super wealthy."
He has connected compassionately with working class Americans over the decades, and reflected that position again Tuesday, stressing that "unions built the middle class."
Biden also movingly recalled the death of his first wife and their daughter in a 1972 car accident weeks before he was to be sworn in as a senator, and praised the work of firefighters who he said saved his two sons who were severely injured in the crash.