Yes, the results of opinion polls are of consequence in that they record the public's opinion on a particular thing, and they can shape the undecided's opinion on that same thing. When a poll is presented as the opion of the public, an undecided individual may find their opinion swayed to the public opinion.
I you see an opinion poll that disagrees with you, you can say "hmm a bunch of nut jobs just happened to all be responding to the same poll". If you see a bunch of polls that all disagree with you, you can say "I bet that this debate site appeals to a different demographic than the majority." If the majority of society disagrees with you, you can find a bunch of like minded people to go a certain website, to vote on certain polls, if that makes you feel better.