Growing numbers of voters are expected to avoid the traditional election-day queues by voting up to two weeks before polling day. Numbers have surged in recent years, with the trend expected to continue during next month's state election campaign.

Victorian Election Commission figures show that during the 2010 state election there were a total of 543,763 pre-poll votes cast, representing 17 per cent of the 3.3 million votes counted. That was almost double the 273,952 pre-poll votes counted during the 2006 state election.

Nationally, the proportion of pre-poll voting has also been rising sharply, from 13 per cent in 2004 to a record 27 per cent in 2013.

The trend has caught the attention of officials from both sides. Victoria now has one of the largest pre-poll votes in the nation. The Victorian Election Commission is believed to now be looking at the balance between the number of pre-poll voting booths and election-day voting booths as a result.

A spokeswoman for the commission said there would be roughly the same number of early voting centres as there was for 2010, although there would be a slight decrease in the number of election-day voting centres.

"The recent changes made to the state electoral boundaries has meant there are a lot less voting centres close to the boundaries," the spokeswoman said. "This has resulted in a decrease in the number of joint voting centres needed."

The Coalition is expected to launch its campaign in the electorally crucial regional centre of Ballarat. The party had considered holding the event in mid-November, but many in the party believe this could be too late.

"This is very different to the 1990s when there were just a few thousand pre-poll votes counted," a senior Liberal Party source said. "This is changing the way we campaign. You do need to front-load campaign announcements, and there are certainly discussions under way about how we might do that."

Traditionally, pre-poll votes have tended to favour the Coalition, although this could be changing. Party officials are also determined not to let the G20 summit in Brisbane, which will held in mid-November, detract from the state campaign.

Meanwhile, Labor strategists believe the party is tracking well in key marginal seats, particularly in Bendigo and Ballarat, although it admits that the fight in Buninyong is tight.

In the crucial sandbelt seats of Frankston, Carrum, Mordialloc and Bentleigh they also believe they are very competitive.

Strategists do, however, acknowledge there are number of Labor seats in which the party is still very vulnerable.

Next week the party's two strategic and campaigning arms – the parliamentary arm and the administrative arm – join for the election.