Is able to vote as several standing initially seek support (7)
I believe the answer is:
canvass
'seek support' is the definition.
(as in to canvass for votes)
'is able to vote as several standing initially' is the wordplay.
'is able to' becomes 'can' (I've seen this before).
'initially' indicates taking the first letters.
The first letters of 'vote as several standing' is 'vass'.
'can'+'vass'='CANVASS'
(Other definitions for canvass that I've seen before include "conduct survey" , "Solicit votes from (electors)" , "campaign" , "Search for support" , "Visit to ask for votes" .)