An election held today would be too close to call, according to the latest figures, with barely any margin separating the Coalition and Labor.

The Liberal-National Party dropped behind Labor in a Morgan Poll released on Monday, the same day Prime Minister Malcolm Turnbull announced a double dissolution election would be called if the Senate could not come to agreement on Australian Building and Construction Commission (ABCC) and Registered Organisations Amendment bills.

It would see Australians vote on July 2 following the federal budget, which was brought forward to May 3.

• Bill Shorten slumps to record low in Newspoll
• Shorten crashes to record low in latest Newspoll
• Tony Abbott improves in latest Newspoll

The polling of 2948 voters, which was taken before Mr Turnbull’s announcement, indicated the government would go into an election as underdogs.

On a two-party-preferred basis, Labor led by one per cent, with 50.5 per cent of the vote, a 3.5 per cent rise, according to the Morgan Poll.

The Coalition remained ahead in primary support, despite a three per cent drop to 40 per cent, while the ALP rose 3.5 per cent in popularity to 33 per cent.

Despite fears legislative changes to the way the public votes in members of the Senate could see some minor parties disappear from the Upper House, public support was reasonably steady.

Primary vote for the Greens increased one per cent to 14 per cent, Nick Xenophon Team dropped to four per cent nationally, while support for Katter’s Australian Party and Independents was unchanged.

The Palmer United Party dipped 0.5 per cent – to zero.

The latest Newspoll, released on Monday morning, put the Coalition ahead 51-49 on two-party-preferred basis.

Mr Turnbull maintained a strong lead over Mr Shorten as preferred Prime Minister at 52-21, and was considered best to manage the Australian economy and tax reform, amid stronger than expected economic growth and a fall in the unemployment rate.

TIMELINE – KEY DATES

APRIL 18
Both houses return to Canberra for three weeks to debate the bills.
Failure to pass the bills will give the government a double dissolution trigger

MAY 3
Treasurer Scott Morrison will hand down the 2016 Budget, seven days earlier than previously scheduled.

MAY 5
Opposition Leader Bill Shorten’s budget in reply.

MAY 11
Deadline day for Mr Turnbull to call a double dissolution election.

JULY 2
The election will be held on this day if the union bills are not passed.