In the same way that Josh Frydenberg is promising GDP growth.
Its called inflation & low unemployment rate
Add to that any Government has the right to put a minimum wage case to the Fair Work Commission. ScoMo opposed a rise to the minimum wage last year. IMO Labor will be advocating a 5% increase to the minimum wage. That covers 2.2 million Aussies.
And add to that the sectors of the Civil Service whose wage increased is tied fully or in part to the CPI.
A mate of mine employs predominantly contractors and their contract rate is tied to the CPI.