His main opponent was George Anderson, the Liberal Reform MP who had held the seat of Waterloo since its creation in 1894.
In one of the closest results of the 1904 election, Dacey defeated Anderson by a mere 117 votes.
At the 1907 election, Dacey defeated sitting MP for Surry Hills Albert Bruntnell.
The resulting by-election in May saw Dacey's son-in-law Simon Hickey easily account for the Liberal Reform's William John Ferguson who was the Member for Sturt from 1894 to 1904.
Hickey increased his majority at the 1913 election and defeated high-profile former state and federal MP Sydney Smith in 1917.