There has to be an election by May anyway, but this could conceivably force an immediate dissolution of Parliament and a general election as soon as possible.
On current polling, the Labor opposition would easily defeat the incumbent conservative Liberal/National coalition government and put trade unionist Bill Shorten into office as Australia's next Prime Minister.
A little background from another article:
The government is looking to block a bid, led by an independent, to allow asylum seekers in offshore camps to come to Australia for medical treatment, saying migrants could exploit it as a way into the country.
Both major parties have long backed tight border protection, looking to keep asylum seekers that arrive by boat out of the country, but Labor has indicated it might back the Medivac bill, which would land an embarrassing defeat of the government in parliament.