A by-election was held for the New South Wales Legislative Assembly electorate of the Clarence on 27 August 1866 following the resignation of John Laycock.[1] 
  Dates
  Candidates
   Results
  1866 The Clarence by-election
Monday 27 August [5]   | Candidate | Votes | % | 
     | John Robertson (elected) | 219 | 57.2 | 
   | Alexander MacKellar | 164 | 42.8 | 
   | Total formal votes | 383 | 98.2 | 
    | Informal votes | 7 | 1.8 | 
    | Turnout | 390 | 18.3 | 
   
 See also
  References
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