Please. Look before you vote.
Voting in the Senate is either very quick and easy, or time-consuming and complicated. The choice is entirely yours.
Unsurprisingly, most people opt for quick and easy.
A little over 96% of voters cast above the line Senate votes at the 2010 Federal election, and that number is, if anything, only going to increase thanks to an explosion in the number of new parties since then.
And that's understandable. Voting below the line requires people to place every single candidate in order of preference - from one to 110 in the case of New South Wales.
It takes time, there are dozens of parties most people have never heard of and the risk of making a mistake and casting an informal ballot is high.
Above the line voting, by contrast, couldn't be simpler.
You just put a one against the name of the party that you want to give your first preference to, and leave them to do the rest.
But that's the catch; if your preferred candidate is eliminated, it's the party and not you that decides where your preferences end up.
Most of the time it doesn't matter, as parties mostly - mostly - try to preference other parties that share their policies and ideologies first.
Every so often, though, a party goes rogue. And that's when voters can end up electing people they never would have dreamed of voting for themselves.
Such was the fate of left-wing voters in Victoria in 2004, when the lead candidate for the obscure Christian-based party Family First, Steve Fielding, was elected to the Senate ahead of Greens candidate David Risstrom.
Fielding had won less than 2% of first preferences - less than one seventh of the votes he needed - but ended up riding the preferences of 11 different parties into office.
You might think of Fielding as the Steven Bradbury of Australian politics.
That's how the system is supposed to work.
With Australia's compulsory preferential voting, no vote is wasted.
Less popular candidates were excluded one by one until Fielding and Risstrom were all that remained in contention for the final Senate seat, and Fielding had more support than Risstrom did.
Fielding was undeniably lucky, but his win was legitimate and the system didn't fail.
Having said that, it's very likely that if every voter had been required to fill out their own preferences, Risstrom would have won and Fielding would never have been a Senator.
Because whilst he was quite a socially conservative candidate himself, Fielding was elected with the help of quite a lot of progressive voters.
Among those 11 parties that had preferenced Fielding over the Greens were the left-leaning Australian Democrats and Labor Party, and it was Labor's preferences that ultimately got Fielding over the line.
This is not what many of their above the line voters would have intended.
Fielding went on to hold a share of the balance of power in the Senate during Kevin Rudd's first term as Prime Minister and, with some irony, became quite a thorn in Labor's side.
How did it happen? As mentioned above, parties usually preference parties that share their values and policy ideas ahead of parties that are opposed to them.
In 2004, that should have seen Labor and the Democrats preferencing the Greens instead of a right-wing Christian party like Family First. But they made a mistake.
Neither would have - perhaps even could have - expected that Family First would still be in contention by the time their preferences came into play. Remember, Fielding got less than 2% of the vote in his own right.
Meanwhile, Both the Democrats candidate and Labor's third candidate (Jacinta Collins, who later returned to the Senate and is now a Cabinet Minister) were considered to be competing with Risstrom for the seat.
Both parties gambled that they would stay ahead of Fielding and receive his votes when he was eliminated, but instead Fielding survived throughout the count and his preferences were never distributed.
Whether you would have preferred Family First or the Greens in the 2004 election, the lesson is the same.
By voting above the line, you lose control of who you ultimately end up voting for.
It could happen again in 2013, and the most likely losers are again progressive voters who would favour Greens candidates.
No fewer than four small progressive parties - the Sex Party, Wikileaks Party, Animal Justice Party and Bullet Train For Australia - have preferenced various right-wing parties ahead of the Greens.
The beneficiaries include the Nationals, Shooters and Fishers, Fred Nile's Christian Democrats and even Pauline Hanson's One Nation.
It's hard to believe that the Sex Party, for instance, really views Hanson as more friendly to its ideas than the Greens.
And Sex Party voters certainly wouldn't think so. But the Sex Party, like the other minor left-wing parties, is just acting strategically in its own best interest.
A preference swap with the Greens might feel good, but it probably wouldn't win them much.
The Greens will go close to a quota in most states without quite winning a seat on primary votes alone.
As a result, it's quite plausible that Greens preferences never actually get distributed to the parties that would receive them.
The smaller right-wing parties by contrast, are at least likely to get knocked out early and pass on their votes to another party.
Assuming it works, it makes good sense to cut a deal with any party you think you're stronger than, in the hope that you can somehow pull a Fielding.
Deals with stronger parties usually won't help you do that. Fielding was just the lucky candidate that beat the odds.
So on a practical level, a little bit of political bastardry with preferences makes good sense.
Each party naturally wants to maximise its chances of winning, and that's understandable.
But that's cold comfort to voters who entrust their preferences to a party and assume they'll send them on to other parties they'd be happy with.
And while this article has focused on the progressive end of the spectrum, the same is equally true among conservative parties.
Katter's Australian Party voters might be shocked to discover that in South Australia, for instance, their preferences will go to Greens Senator Sarah Hanson-Young ahead of both the Liberals and Labor.
The only sure way of controlling where your preferences end up is to fill them in yourself, by voting below the line.
I will be doing that, and recommend that you do too.
But if you still intend to vote above the line, please take the time to look up where your preferences could end up.
You can view the group voting tickets - which determine above the line preference flows - on the AEC website by clicking HERE.
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