Can the Australian Greens Replace the Australian Democrats as a 'Third Party' in the Senate?

In this article I discuss the likelihood of the Australian Greens being able to develop into a party that plays an equivalent 'third party' role in the Senate similar to that played by the Australian Democrats for most of their existence. My conclusion, based on attitudes underlying voting behaviour, is that they cannot afford to behave contrary to their position as part of a left-wing bloc without jeopardising a substantial part of their voter base. [ABSTRACT FROM AUTHOR]