at its creation in 1984, mayo was a rural electorate that stretched from the seaside town of victor harbor to the adelaide hills, which had previously been represented mostly by the seats of barker and boothby. a safe liberal seat, it began with a notional 12.3 per cent liberal two-party margin ahead of the 1984 election. liberal alexander downer, fifth and latest of the downer family political dynasty, notionally retained mayo for the liberals and would hold the seat for 24 years.