Turnbull can't be accused of an ambush of the crossbench because the Senate will now have plenty of time to consider the two workplace bills that will be the triggers for the double dissolution if they are not passed. Malcolm Turnbull faces dangers at every turn. Credit:Nic Walker On one level, he can't lose: if the crossbenchers buckle, he can claim victory and reset the election for September or October. If they hold firm, as seems certain, he has a platform for a campaign that is his to lose. On another level, this is a colossal gamble by a Prime Minister whose approval rating lead over Opposition Leader Bill Shorten has narrowed dramatically after months of perceived drift, mixed messages and internal tensions. The truth of it is that Turnbull had little option but to act. Having identified public opinion polls as his main justification for tearing down former prime minister Tony Abbott, he simply - and urgently - had to address the trend of recent polls.

According to Newspoll, Turnbull has taken six months to do what Tony Abbott did in three: have more voters unsatisfied with his performance as prime minister than satisfied. The saving grace is his still huge, 30-point lead over Shorten as preferred prime minister. This is a play that gives new meaning to the term "telegraphing one's punches". The last PM to gamble this way was Julia Gillard, who announced a September poll in January 2013 and didn't survive to lead Labor into the campaign. Turnbull is giving 15 weeks' notice of polling day, when the polls give the Coalition only a narrow edge in two-party terms and those who breathed sighs of relief when he became Prime Minister are wondering what he stands for.

Turnbull's message is that the perceptions of dithering are just that. He had a plan to seize back the agenda and was waiting for the right moment to strike after securing the passage of Senate voting reforms. His aim is clear: to stop the damage to the Coalition that flowed from his promise of sweeping tax reform unravelling; Labor's ambitious policy agenda on multiple fronts; and the dysfunction of the Abbott administration being so clinically dissected by journalist and former Coalition staffer Niki Savva. Turnbull defines the contest as about which side of politics has the better plan to transition the economy after the mining boom. He insists the restoration of the Australian Building and Construction Commission is critical to the Coalition's plan for jobs and growth, productivity and prosperity. The irony is that this is very much an Abbott strategy, based on instilling fear in voters about Labor's links to union thugs and Shorten's changes to negative gearing. Labor will cast it as a replay of John Howard's attempt to impose WorkChoices through a compliant Senate. One problem is that workplace relations was not even mentioned when Turnbull announced his intention to challenge Abbott six months ago and promised a different style of economic leadership.

Another is that there is now little or no prospect of tax relief in the budget, when Treasurer Scott Morrison and Tony Abbott before him raised expectations that relief, at the very least to address bracket creep, would be front and centre of the Coalition's economic plan. But the bigger problem would have been to allow the perception of drift and indecision to continue. As election analyst John Stirton observes: "While any early election is always risky, the Prime Minister can't really address his problems without an election and so that probably means, from the PM's point of view, the sooner the election the better." Effectively, Turnbull has drawn a line in the sand. He is banking on his ability to beat Shorten in a head-to-head, 15-round title fight that will be as much about self-discipline and stamina as ideas. Loading

Not a moment too soon; certainly from Turnbull's point of view, it's game on. Follow us on Twitter