The president said his nominee to fill the late Justice Ruth Bader Ginsburg's seat "will be a woman."
He also praised Minnesota supporters' "good genes," adding: "A lot of it is about the genes," in a troubling, disjointed rally speech.
The ad uses an image of Biden, captured during an emotional moment as he spoke of the challenges of caring for sick family members, to label him as "weak."
Scalia and Ginsburg might have had different political views, but the pair shared a jovial camaraderie, as well as mutual respect for U.S. law.
“I think we’re too close to the election," one Republican senator said about then-President Barack Obama's Supreme Court pick.
The package was intercepted before it reached the White House, law enforcement officials said.
In the wake of Ruth Bader Ginsburg's death, the Maine Republican senator said the next Supreme Court justice should be picked by the winner of November's presidential election.
A number of anti-abortion politicians and activist groups see their goal of ending nationwide abortion rights in sight.
The Senate Judiciary Committee chairman previously has said such vacancies should not be filled during a presidential election year.
ActBlue, a nonprofit that raises funds for Democrats, received more than $12.5 million in the two hours after news broke of Ginsburg's death.