Wealthy donors give money to politicians who they believe share their ideology and so they would like to see them in government so they donate money thats how the system works everywhere. The people who give to Romney also like Bibi's ideology and so they are also giving to him, its not illegal. Bibi of course has to say he doesn't support anybody in the US thats simple diplomacy but everybody knows full well Bibi supports Romney both because Obama has been terrible for Israel and Bibi doesn't want another 4 years of him and also he is a personal friend of Romney. Bibi might not be handling the diplomatic side of things to well because he has been to openly pro Romney but he is not committing a crime and he should not be condemned for supporting Romney.
Army: Blast in Korean DMZ wounds two South Korean soldiers (Reuters)
from the article: Netanyahu and Romney share ideology - and donors