An incoming Labor government will struggle to legislate its key tax increases with almost the entire Senate crossbench opposed to its plans to abolish cash refunds for excess franking credits, and none prepared to support the limiting of future negative gearing to newly constructed homes.

In addition, a Labor government could also struggle to find support to lift the top marginal tax rate by 2 percentage points and unwind stages two and three of the income tax cuts, which have already been legislated.