Yes one can manipulate the polls.

Yes, as rightly pointed out the polls can be manipulated ( I never did manipulate). I learnt from that person who accussed me of cheating and making Alan lead in the polls. I didn't believe him/her at first but have discovered one could actually vote many times from one's computer or laptop etc. It's quite a tedious process though.

I would like to thank that person for teaching me.
Since, the polls could be manipulated I've decided to delete them and not to used them again.