“From early childhood, he formed his views through observation and analysis, by hanging back as the world unfolded before him,” Michael Kranish and Scott Helman write in “The Real ­Romney.”

David Maraniss, whose biography, “Barack Obama: The Story,” will be published in June, describes the president in similar terms. Much like his mother, “Obama is an anthropologist — a participant/observer,” Maraniss, a Post associate editor, told me.

Both Obama and Romney exude cool detachment, even insularity, as The New Republic’s Timothy Noah demonstrated with an array of indistinguishable snippets from “The Real Romney” and Jodi Kantor’s “The Obamas.” They are not party animals, in either sense of that phrase — neither extroverted socializers nor partisan champions.