We learn from the Edwin M Wright interview which is archived at the Truman Online Library that an American Jew working at the State Department was calling around presidents of many countries pretending to be President Truman himself and he was telling them that he wanted them to vote in favor of partition – and if they refuse – the American funds that were promised to them would not be sent to them. Some of them believed that it was Truman himself who was talking to them and therefore, they changed their vote which made it possible for Palestine to be partitioned. Here is the link:
trumanlibrary.goV/library/oral-histories/wright