Imagine a large majority of people in your state wanted to eliminate all taxes, even if that meant that the government could no longer fund such things as a police force or road repairs. your state’s senator would be acting as a(n) if she decided to vote to eliminate all taxes simply because the people have demanded it.

If she agrees with the tax elimination, she is carrying the voice of a majority group,  in this case, those who are in favor. She is acting in a delegate role. So the correct word to fill the blank is delegate.

Explanation:

She is the delegate because she is speaking on behalf of a group of persons with a specific request and in addition to this, she is in favor.