Cain's Iowa polls "markedly lower"

From the AP:

Private polling shared with The Associated Press shows Cain’s support has declined in Iowa since last month. Internal polls of likely Republican caucusgoers showed Cain’s support consistent with The Des Moines Register’s poll in late October, which showed Cain narrowly leading in Iowa with 23 percent. The private polls showed Cain’s Iowa still in double digits, but markedly lower.