user: Question: Where is the poll source when Hillary Clinton was the democrat, John McCain was the republican, and the margin of error was less than 4.5 on May 2-7, 2007?
Columns: ['Poll Source', 'Sample Size', 'Margin of Error', 'Date', 'Democrat', 'Republican']
Types: ['text', 'real', 'real', 'text', 'text', 'text']
Sample row: ['Quinnipiac', 1697.0, 2.4, 'Mar 19-24, 2008', 'Hillary Clinton', 'John McCain']
SQL:

assistant: SELECT "Poll Source" FROM "Table" WHERE "Democrat" = 'Hillary Clinton' AND "Margin of Error" < 4.5 AND "Republican" = 'John McCain' AND "Date" = 'May 2-7, 2007';