Welcome to POLITICO’s West Wing Playbook, your guide to the people and power centers in the Biden administration. With help from Allie Bice.   Send tips | Subscribe here| Email Eli | Email Lauren PROGRAMMING NOTE: We’ll be off this Monday, Feb. 20 for Presidents Day but will be back in your inboxes on Tuesday, Feb. 21. We hope absence makes the heart grow fonder. It’s not unheard of in modern American politics for an incumbent president to face a primary challenger. RONALD REAGAN ran against President GERALD FORD in 1976, TED KENNEDY took on President JIMMY CARTER in 1980 and PAT BUCHANAN ran against President GEORGE H.W. BUSH in the…