I hold both Canadian and American citizenship. I don't see why getting a Canadian passport would be a problem. Present your Canadian documentation (ie your birth certificate) with your application and you should be fine.... Canada recognizes duality... The U.S. tolerates it but doesn't seem to 'officially' accept it.

I even had a U.S. Immigration offficer point out how convenient it must be to use a Cdn passport going to T.O. then switch to my U.S. passport when returning (I thought I was doomed when he said that, but then he just wished me a good flight and off I went) ^


Edited to add: It is my understanding that unless you formally relinquish your Cdn Citizenship, you continue to be considered a citizen and are due the priviledges and drawbacks that go along with it.