The election vote is always biased

Theoretically, no single vote will change the final result. However, this belief is commonly known and could result bias of the election result. The expected minority group has more intention to vote than the expected majority group, thus a greater proportion of the expected minority group will vote. Thus the final result does not show the real opinion of the public and is biased towards the expected minority group. Based on this thought, we could expect that the election result of Brexit may be biased towards the "Exit", the expected minority.