Writings or public statements advising elected politicians on how to make hard choices

While not always seen in this light, members of congressional or parliamentary bodies are regularly faced with moral choices when deciding how to vote in situations where the answers to questions like the following may point to diametrically opposed courses of action.

1. What's best for my country?
2. What's best for those whom I represent?
3. Whats best for those who voted and/or may vote for me?
4. How to best hold on to this incredibly powerful microphone which is so personally rewarding to use?
5. How best to pay for my kids' education in expensive schools, several houses and cars, etc...

Are there scholarly works (books, monographs, memoirs) by those who study this conundrum or have faced it personally that provide guidance to others who may face it?

update: In the absence of answers with those (this question is now six months old), are there at least clear public statements about how elected officials that provide such guidance?