If you're a respectful, decent human being the majority of us will like you. Granted we also tend to dissect a person culturally to better understand them, but don't take that as an offense, it's genuine curiosity and friendliness.
Now, in some states and (especially) cities you might run the risk of some stupid asshole making a derogatory comment about you, your country, your leaders, or your nation's history. However, especially in the smaller-town/city areas of New England and the Midwest, if you assert yourself as a decent, well-standing human being, people will treat you very well, or at the very least normally.
As a fair warning on the whole derogatory statements thing: Some people believe Russia is still a fully-fledged communist state. Elderly people might call you a communist. Others may call you a damned Red or "Ruski" ("proper" spelling russkiye / русские). Just shrug it off and avoid those people. Again, if you assert yourself as a decent human being who is willing to accept American culture and ways of life, then you'll be just fine.
On another note, what kind of Pennsylvanian community are you planning to live in? Small mining/transport/farming community? City suburb? Inner-city apartment? How fancy or extravagant are you planning to live?