So the 68%  of Australians that do profess to be Christian should not partake in the federal elections? Nor have representation of their choosing? The 72.8% of people that profess a religious belief should stand aside and let themselves be dictated to by a minority?
Also, don't forget that your 28% (27.2% according to ) also includes people who didn't answer the religion question adequately (poor handwriting etc.), so the number of 68% Christians, should be considered the *minimum* percentage of society that expresses a belief that they're Christian (similarly for the other religions).
It's a democracy. Deal with it. Start your own party if you like, the AEC  would be glad to help you, that's what they're there for.
For the record, I'm a Christian and I don't vote for specifically Christian parties because they're all conservative and I'm liberal.I disagree with much of the policy of the Christian parties as it pertains to technology. I still fail to see how the Christian lobby is the problem. It's successive ministers from both parties who have shown, on a global stage, that they are utterly uneducated and inept in the realm of modern technology.
It's about technology and government, not religion.