Even in a Republic the representatives of the people are expected to vote to reflect the will of the people who put them there.
Is that not exactly why we have elections? to have the opportunity to vote for those who will go to Washington and represent our wishes?
How do we know the polls aren't manipulated by liars? You can't base your decision on either lying polls or whims of the people which are controlled by media.
Majority rule can be brutal (just look at the French Revolution), especially when it is based on polls which change daily. This is why the Bill of Rights was created...to protect the minority.
Yes, we have democratic values but we don't have pure democracy. Thank God.