using CMS.Polls;

using CMS.SettingsProvider;

using CMS.DataEngine;

using CMS.GlobalHelper;

...

      string pollName = "testingpoll"; // Testing poll code name

      // Get poll info by code name

      PollInfo pollObj = PollInfoProvider.GetPollInfo(pollName);

      if (pollObj != null)

       {

          // Set the field values

           pollObj.PollResponseMessage = "Thank you for your time.";

           pollObj.PollAllowMultipleAnswers = true;

          // Save the changes

          PollInfoProvider.SetPollInfo(pollObj);

       }