A council media statement said that Ms Whitehead received 1849 votes, ahead of retired lawyer and former councillor Phil Wilson (1590 votes) and businesswoman Emily Rutherford (408 votes).
Ms Rutherford's name was on voting papers despite announcing in April that she had stopped campaigning.
The voter return was 26.49%, being 3843 votes.
There were four special votes still to count, the statement said.