Is Market Research a Science?

I am sharing this because it struck me just now. We often wonder how accurate is market research. We have all done some or the other surveys. We often wonder whether the info gained is truly representative of the ground reality. Sometimes we try and moderate down some extreme finding because it feels so contrary to our intuition. This is just the context.
I was going through some survey conducted by CNNIBN on voter sentiment. Then I remembered that all the news channels make electoral predictions based on "extensive, scientific" market survey and then when the results are out, often the predictions are way off the mark.
Key point: Elections seem to be the only scenario where the survey results and actual ground reality can be compared to see the effectiveness of the survey. Could this not be used to zero in on to the best practices in questionnaire making, survey conduction etc? In fact, we ultimately may find out that Market research too, like the rest of the marketing is more of an art, and not science.
P.S. Please mention, if possible, other scenarios where survey result and actual ground reality can be objectively compared. Generally, one never gets to know the ground reality though one might often get close to it(indicated by success of some strategy based on survey findings