<Tr> <Th> Majority Leader </Th> <Td> Mitch McConnell (R) Since January 3, 2015 </Td> </Tr> <Tr> <Th> Minority Leader </Th> <Td> Chuck Schumer (D) Since January 3, 2017 </Td> </Tr> <Tr> <Th> Majority Whip </Th> <Td> John Cornyn (R) Since January 3, 2015 </Td> </Tr> <Tr> <Th> Minority Whip </Th> <Td> Dick Durbin (D) Since January 3, 2015 </Td> </Tr>

Which of these is not a requirement to be a united states senator