Polls show that if he was elected as an independent senator, Matty could hold the balance of power in a future Rudd government.

Matty has consistently refused to disclose his intention to stand at the next federal election, instead calling for Kevin Rudd to "bring it on". Matty has also refused to back any future Abbott-led government, despite his stated preference for Mr Abbott as Prime Minister.

Matty, a former member of the Greens and ex-One Nation supporter, could prove to be the wild card in the next term of government. Matty has refused to discuss any preference deals with other minor parties and independents.

Sources say that a key policy area for Matty is animal welfare. They say that Matty would need to see each party's policies on protecting animals before he made the decision to trade his vote on other issues.

Thoughts?