WASHINGTON — President Joe Biden is expected to discuss the future of his re-election campaign with family at Camp David on Sunday, following a nationally televised debate Thursday that left many fellow Democrats worried about his ability to beat former President Donald Trump in November, according to five people familiar with the matter. [Snip] So far, the party’s top leaders have offered public support for Biden, including in tweets posted by former presidents Barack Obama and Bill Clinton. Senior congressional Democrats, including Reps. Hakeem Jeffries of New York, Jim Clyburn of South Carolina and Nancy Pelosi of California, have privately...