Many people have speculated why a first term government is in such danger of losing this Saturday night. Perhaps the simplest explanation is that, all other things being equal, Victoria is a naturally Labor state.

Yet, Victoria was once considered the jewel in the crown of the Liberal Party. Not only did the Liberals hold office at state level from 1955 to 1982, they dominated in Federal elections in Victoria in the same period. In the ten Federal Elections from 1955 to 1977, the Coalition won the two-party preferred vote in Victoria in eight of them, with 1972 and 1974 the only exceptions.

Around 1980, this completely changed. From 1980 to 2013, there have been 13 Federal Elections and, in Victoria, the Coalition has only reached 50 per cent of the two party preferred vote twice, in 1990 and 2004. In the same period, there have been nine State Elections, with the Liberals winning the two party preferred at four of them (1988, 1992, 1996 and 2010).

So, in a total of 22 elections (Federal and State) in Victoria since the start of the 1980s, the Coalition has secured a majority of the popular vote just six times, compared to Labor’s 16.

Thus it could be argued that, unless there are exceptional circumstances, we might consider that the natural starting point for an electoral contest in Victoria is not 50-50, but more like 52-48 in Labor’s favour.

Looked at that way an incumbent Coalition cannot rely on getting returned after doing a reasonable job in its first term. It actually has to be exceptionally strong to overcome the in-built Labor bias in Victoria.