The Senate is gearing up for fiery late night debate as the federal government vows to get a vote on two contentious bills this week.
The government wants a vote on its 10-year company tax cuts package and controversial changes to race-hate speech laws on Thursday, before parliament rises for a month-long break ahead of the May budget.
Debate could roll into Friday as neither bill has sufficient support to get through the upper house.
The proposed changes to the Racial Discrimination Act would swap the words "offend", "insult" and "humiliate" to "harass and intimidate".
It does not have the support of Labor, Greens, the Nick Xenophon Team or Jacqui Lambie, robbing the government of the 38 votes it needs to get it through the upper house.
Meanwhile the government is insisting it's still committed to implementing its 10-year tax cut plan, despite lacking support in the Senate.
With Labor sticking to its opposition to a broad tax cut and limiting the reduction to 27.5 per cent for firms with a turnover of $2 million or less, the government needs the support of a fractured crossbench.
The government can expect support from independent senator Cory Bernardi and Liberal Democrat David Leyonhjelm, but Pauline Hanson's four One Nation senators will only support a reduction for businesses with a turnover of up to $50 million.
Senator Xenophon will back a reduction for businesses with a $10 million turnover, as will independent Derryn Hinch.
Debate on the company tax cuts was postponed on Wednesday as Senator Xenophon needed to leave Canberra after suffering a family bereavement.
Treasurer Scott Morrison was coy on whether the government would be splitting the company tax cuts bill so some measures will pass.
"All of your questions on that will be answered by the experience of the next 24 hours," he told reporters on Wednesday night after announcing a code of conduct for the sugar industry following an ongoing dispute between marketer QSL and miller Wilmar in Queensland.
Senator Hanson briefly went on strike on Monday, refusing to vote on any legislation in the Senate because of sugar industry row and demanding it be resolved through a mandated code of conduct.