President Joe Biden on Friday announced that he will nominate former Food and Drug Administration (FDA) Commissioner Dr. Robert Califf to once again head the agency. Califf, who was commissioner for nearly a year starting in February 2016, “is one of the most experienced clinical trialists in the country, and has the experience and expertise to lead the Food and Drug Administration during a critical time in our nation’s fight to put an end to the coronavirus pandemic,” Biden said in a statement. The post has been filled on a temporary basis by Dr. Janet Woodcock since the president entered office in January. Several Democrats could oppose the nominee, considering three did the last time the Senate considered him. Sens. Richard Blumenthal (D-Conn.), Joe Manchin (R-W. Va.), and Edward Markey (D-Mass.) voted against making Califf head of the FDA, arguing the agency needed an overhaul and promoting somebody from within …