Joe Biden and Kamala Harris made an upbeat show of unity Thursday as they held their first joint public event since Harris replaced the president as the Democratic candidate in November's election.
Chants of "thank you Joe!" rang out from the audience at a community college in Maryland, near Washington.
Biden was celebrated as he took credit for a major deal to reduce medicine prices for retirees on social welfare programs.
But the biggest star was Biden's vice president who has united the Democratic Party and surged ahead in the polls against Republican Donald Trump since her abrupt entry into the race.
"She can make one hell of a president," Biden said of Harris.
The joint appearance came a couple hours before Trump was due to hold a press conference at his golf club in New Jersey.
The real estate billionaire and scandal-engulfed former president has struggled to pivot his campaign since Biden dropped out on July 21, amid Democratic concerns that he lacked the stamina at 81 to do the job.
Until then, Trump was rising steadily in the polls, in large part on his message that Biden was losing his mental acuity -- a charge which gained currency when the president badly flubbed a televised presidential debate.
Now it's Harris, 59, who has the growing momentum against 78-year-old Trump.
And Biden, in the lame duck end of his four-year term, appears reenergized, embracing the role of mentor handing off to his protege.
In his speech, Biden said the Democrats' plan was to "beat the hell out of" Republican opponents and he prompted laughter on pretending not to know Trump's name -- "Donald Dump or Donald whatever."
Harris, set to be crowned as Democratic nominee at the party convention in Chicago next week, made a display of vice presidential deference, delivering only short remarks and stressing that it has been her honor to serve under the "most extraordinary human being."
"There's a lot of love in this room for our president," she said to cheers.
The drug prices deal will reduce costs for retirees on 10 key medicines, including treatments for diabetes, heart failure and blood clots.
The scope and timing of the deal -- which the White House says will save older Americans $1.5 billion and the Medicare federal health insurance scheme $6 billion in the first year -- is a boost for Harris in an election where cost of living is a major issue.
In a statement, Harris called the negotiations with pharmaceutical companies "historic" and "life changing."
Americans face the highest prescription drug prices in the world, leaving many people to pay partly out of their own pocket, despite already exorbitant insurance premiums.
On Friday, Harris will for the first time lay out details of her economic platform.
The United States' first female, Black and South Asian vice president is expected largely to stick to Biden's economic agenda, while trying to differentiate herself, avoiding voter wrath over the post-Covid pandemic surge in inflation.
Axios reported Wednesday that Harris wants to "break with Biden on issues on which he's unpopular," with rising prices being top of the list.
While Trump has long polled more strongly on the economy, a recent poll from the Financial Times and University of Michigan found voters trust Harris more on the issue, by 42 to 41 percent.
Trump, who survived an assassination attempt on July 13, is now the oldest presidential nominee in US history.
He did not say what would be the topic of his press conference in New Jersey. In a speech on Wednesday, he veered from prepared remarks about the economy to repeated personal insults against "crazy person" Harris, "stupid" Biden and calling Harris's running mate Tim Walz a "clown."
