The Washington Post reported:
Former president Barack Obama, at a private lunch with President Biden earlier this summer, voiced concern about Donald Trump’s political strengths — including an intensely loyal following, a Trump-friendly conservative media ecosystem and a polarized country — underlining his worry that Trump could be a more formidable candidate than many Democrats realize.
At the lunch, held in late June in the White House residence, Obama promised to do all he could to help the president get reelected, according to two people familiar with the meeting, who spoke on the condition of anonymity to discuss private conversation.
That commitment was a welcome gesture for the White House at a time when Biden is eager to lock down promises of help from top Democrats, among whom Obama is easily the biggest star, for what is likely to be a hard-fought reelection race. The contents of the private conversation have not been previously reported.