traveled from delaware to washington this weekend for a secret meeting with influential liberal senator elizabeth warren. she s the leading voice. i m not surprised they will seek her counsel. reporter: the massachusetts senator has refused to endorse front didn frontrunnerner hillary clinton. i want to see all of the presidential candidates lay out where they stand on key issues. reporter: biden associates see a possible opening because clinton has been battling a trust issue. did you wipe the server? with a cloth or something? reporter: the latest orc poll shows 53% have an unfavorable opinion of clinton while 44% view biden that way. bernie sanders sees clinton s numbers as helping him. where he gaining. what the polls seem to indicate is that hillary clinton support seems to be receding.