I believe Zogby’s polling is over the internet. When I participated in it, I would get an email.
I never was contacted by them. Maybe for this purpose they use only emails now.
Their Zogby website says:
Zogby Analytics provides several services related to public opinion and market research. Our talent lies in providing the following types of research:
Research Methodologies
Live Operator Telephone Polling
Automated Telephone Polling
Internet-based Polling and Online Surveys
Customer Satisfaction Surveys