Coming soon : love letters between Warren Harding and his mistress . `` I know now of my failure . The 15-year affair ended before Harding became president in 1921 . Hide Caption 1 of 10 Photos:Photos: A book on the affair examines its possible historical impact .
Coming soon : love letters between Warren Harding and his mistress . The 15-year affair ended before Harding became president in 1921 . Hide Caption 1 of 10 Photos:Photos: A book on the affair examines its possible historical impact .