Ignore the national polls: Biden is a gift to Republicans for as long as he stays in the race

Every piece of data, every supportive “Ridin’ with Biden” social-media post, every delusional quotation from elected leaders and party hacks that tells people to ignore what they see and hear and focus on some sepia-tinged “legacy” for the president keeps the weakest Democratic candidate for re-election since Lyndon Johnson on the ticket.