<Tr> <Th> Poll source </Th> <Th> Date (s) administered </Th> <Th> Sample size </Th> <Th> Margin of error </Th> <Th> Jeff Flake (R) </Th> <Th> Generic Democrat </Th> <Th> Undecided </Th> </Tr> <Tr> <Td> Public Policy Polling </Td> <Td> July 31--August 1, 2017 </Td> <Td> 704 </Td> <Td> ± 2.0% </Td> <Td> 31% </Td> <Td> 47% </Td> <Td> 22% </Td> </Tr> <Dl> <Dt> with Matt Salmon </Dt> </Dl> <Dt> with Matt Salmon </Dt>

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