Helmut Norpoth is co-author of  The American Voter Revisited, covering the images of presidential candidates, party identification, and why Americans turn out to vote.  He has also written a book about public reactions to British Prime Minister Margaret Thatcher, especially her economic and foreign policies.  Norpoth has designed models to forecast elections in the U.S., Britain, and Germany. His Primary Model correctly predicted Obama's re-election as early as February of 2012 and correctly predicted that Donald Trump would be the next President of the United States.