When you have a problem with one particular site, a good "first thing to try" is clearing your Firefox cache and deleting your saved cookies for the site.
1. Clear Firefox's Cache
Edit > Preferences > Advanced > Network
Under Offline Storage : "Clear Now"
2. If needed, delete the site's cookies here
While viewing a page on the site, right-click and choose View Page Info > Security > "View Cookies"
You also can change the search box at the top of the dialog to look for any polldaddy cookies.
Then try reloading the page. Does that help?
If that doesn't help, I wonder whether any of your other add-ons could be interfering? A standard diagnostic for that is to try Firefox's Safe Mode.
First, I recommend backing up your Firefox settings in case something goes wrong. See Back up and restore information in Firefox profiles. (You can copy your entire Firefox profile folder somewhere outside of the Mozilla folder.)
Next, restart Firefox in Firefox's Diagnose Firefox issues using Troubleshoot Mode using
Help > Restart with Add-ons Disabled
In the Safe Mode dialog, do not check any boxes, just click "Continue in Safe Mode."
If the poll appears, this points to one of your other add-ons or a custom setting as the problem. Maybe an ad blocker?