US President Joe Biden is facing mounting pressure from within the Democratic Party to step aside as the presidential candidate following concerns about his age and performance, with odds of him being the nominee dropping significantly. Speculation and betting markets indicate a decreasing likelihood of Biden winning the election, prompting discussions about his potential withdrawal and its implications, including the impact on Vice President Kamala Harris and the VP candidate selection. Biden's recent Covid diagnosis has added complexity to the situation, with Democratic leaders reportedly urging him to pass the baton, leading to a self-isolating stance both medically and politically.