I seem to recall a different poll reflecting the opposite results—strongly against masks, but it may have been a question re: mandatory masks, which is NOT the same as a poll favoring the use of.
The Hill-HarrisX poll showed 68% support mandatory public face masks in some capacity.
Forty percent said the coverings should be required both indoors and outdoors;
28% said they should be mandatory for indoor activities only.
Twenty-two percent said they should be recommended but not mandatory;
6% said never recommended and 5% were uncertain.