Irrespective of how polls are being conducted (I am talking about political polling), the representative nature of the resultant polling results speak for themselves over time.
In Australia, such polls in recent years have been fairly good in gauging public opinions. In the past 2 or 3 federal elections, NewsPoll's and MorganPoll's survey on polling intentions had been fairly close to the actual election results.
If they had been wrong in the majority of times, they would be out of the business of political polling in no time.
