So my question is, should I make individual tables for each member to keep track of their a poll (many tables since many members) or have the poll data inside a single table--therefore many polls would be many rows.

I'd use a single table, and would add a secondary, non-unique index on member id. (Without the secondary index, any search that included the member id would be linear through the entire table. With the index, you're searching a much smaller subset of the table.) Using one table gives you the benefit of (probably) keeping much of the index in the operating system's disk cache. That'd be a bit harder with lots of small tables.