In the last few weeks, as the Labor two party preferred vote has come back to 46 or 47 and the Coalition vote has shrunk to 54 or 53, Labor have come into around $3.50, while the Coalition has widened out to around $1.30.
I say the odds are "around" those levels for as far I can tell, there are 6 agencies betting on the election - Centrebet, Sportsbet, Sportingbet, Betstar, Tom Waterhouse and Betchoice. [Please let me know if you find any more.]
As things stand, Betstar and Tom Waterhouse are offering the best odds on a Coalition win at $1.35, while Sportingbet has Labor at $3.75.
The election is just under two years away. Polls will swing, a few dollars will be invested and inevitably, these odds will also swing around. I wouldn't be at all surprised if at some stage over the next two years, the Coalition's odds will widen, meaning that clever punting can lock in a guaranteed profit. As it is, betting on Labor with Sportingbet and taking the Coalition with Betstar or Tom Waterhouse can lock in a tiny profit (not worth it now given the cost of carry - interest in other words).
But plonking a few dollars on Labor now at $3.75 and then jumping on the Coalition when they blow out past $1.50 (hopefully you can get even better odds at some stage), you can guarantee a nice profit, which ever party wins the 2013 election.
I will create a paper election betting portfolio that I will update hopefully to show my logic:
$100 on Labor at $3.75.