text:  But a strong finish. He may not finish as the party's nominee, as we hear from Fox's Chad Pergram. Last night was seismic. A senior House Democratic leadership source tells me, quote, those closest to the president have not served him well. The source adds, quote, this is not sustainable. Now, removing the president is messy. It would likely take a cohort of senior Democrats ranging from former presidents Obama and Clinton to former House Speaker Nancy Pelosi to convince Mr. Biden to step aside.