WASHINGTON — Three days after his crushing loss last November in the attorney general’s race, Richard Cordray received a call from the Harvard law professor who is building the first federal agency to police consumer financial products. Would you like to join the agency, Elizabeth Warren wanted to know? Even though Cordray was “reluctant to think of anything’’ in the aftermath of his defeat, he found the idea “intriguing,’’ and within a month he accepted the offer to become director of enforcement at the Consumer Financial Protection Bureau. Today Cordray finds himself near the center of a storm that dwarfs anything he faced in Ohio politics.