What is a senator who votes based on what she thinks is best for her constituency is called a?

delegate senator.

A delegate senator is a representative who votes in accordance with the preferences of their constituency, rather than based on their own personal beliefs or party affiliation. This type of senator is often seen as a servant of the people, whose primary responsibility is to accurately reflect the wishes and interests of those they represent.

Delegate senators typically engage in extensive communication with their constituents, in order to gather input and feedback on issues before making voting decisions. They prioritize being responsive to the concerns and needs of the community, and may seek to build strong relationships with local organizations and leaders to stay informed about the issues that matter most to their constituents.

While delegate senators may not always align with their party's platform or the preferences of special interest groups, they are committed to making decisions that they believe will benefit the majority of their constituents. By prioritizing representation and accountability, delegate senators aim to ensure that the voices of the people are heard and reflected in the legislative process.