Five candidates are contesting the two seats available on the board of Onchan Commissioners today (Wednesday).
They are finance sector worker Rob Callister, retired accounts administrator James Corrin, chartered accountant John Quaye, port security officer Robin Turton and disability awareness trainer Kathryn Williams.
The by-election was caused by the death of long-time Island politician Ray Kniveton and the resignation of Brian Stowell last month.
The polling station at the Onchan Youth and Community Centre in School Road is open until 8pm.
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