Hang One's Hat On Meaning

Example : 1998 Oct. 16, Saul Hansell, "Zap, a Nervy Internet Venture, Is Zapped," New York Times (retrieved 8 Nov 2015):  "You can't hang your hat on a nonbinding letter of intent."2013 March 26, Jessica Danielle, "Sports Notes," Ebony (retrieved 8 Nov 2015):  The Nuggets don't have the most dynamic offense nor do they have a real superstar to hang their hat on but their defense is strong.2015 April 10, Bob McWilliams, "Plain Speaking: GOP field of candidates is diverse," Capital Gazette (retrieved 8 Nov 2015):  So far, all we've heard is "Don't you want to see a female president." . . . [I]t's easy to see why Clinton has little else to hang her hat on. She has no real achievements to speak of in her term as senator.