Tried hard (6)
I believe the answer is:
strove
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">tried hard</span>' is the definition.<br/ ><span class="explanation-format__explanation">(past tense of 'strive')</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for strove that I've seen before include "Endeavoured" , "Voters (anag) - made every effort" , "Struggled" , "Tried hard for voters" , "Made great efforts" .)