US President Joe Biden has admitted he made a "mistake" in last week's debate against Donald Trump but vowed to fight on in the election race and took steps to reassure key allies.
On Wednesday, as reports emerged that he was considering his future, he worked to placate senior Democrats, including state governors and campaign staff.
Speculation has mounted over whether she could replace the president as the party's candidate ahead of the November election.
A New York Times poll conducted after the debate, published on Wednesday, suggested Trump now holds his largest lead ever of six points
These include Massachusetts-based Indian-American industrialist Ramesh Kapoor, who has been raising funds for the Democrats since 1988.
Amid speculation, Trump's comments indicate he may turn his focus to attacking Ms Harris.
Newsom's pitch at local Independence Day picnic is part of an effort by Biden's reelection campaign and the White House