I said it's possible that there is a voluntary response bias. We know Zogby had target demographics (age, location "likely Democratic voter"), but we don't know how respondents were selected other than that the poll was conducted randomly online over 2 days.

if you had any clue about polls, you would know

they are selected the same way that normal polls are

http://www.people-press.org/methodology/collecting-survey-data/internet-surveys/

people cannot just decide to participate, therefore there cannot be a voluntary response bias

https://stattrek.com/statistics/dictionary.aspx?definition=voluntary%20response%20bias

In survey sampling, voluntary response bias occurs when sample members are self-selected volunteers, as in voluntary samples .

you dont know what you're talking about, and clearly havnt spent even a minute or two googling anything trying to find out

well done

its always amusing how people who have no clue about polls, state that a poll is worthless because of X