Newly elected American Republican starts being mean (4)
I believe the answer is:
near
'being mean' is the definition.
(both can mean miserly)
'newly elected american republican starts' is the wordplay.
'starts' indicates taking the first letters.
The initial letters of 'newly elected american republican' is 'NEAR'.
(Other definitions for near that I've seen before include "Approaching" , "A short distance away" , "Nigh" , "unlikely to spend much?" , "Verging on" .)