Australia’s first woman prime minister has boosted the government’s once—lagging popularity to an election—winning lead over the opposition, according to a respected opinion poll published on Monday.

Prime Minister Julia Gillard’s early public support since she ousted her predecessor Kevin Rudd in a shock leadership challenge last Thursday could tempt her to call an election soon.

The survey by Newspoll, a Sydney—based market research company part—owned by News Corp., found that the center—left Labour Party government’s public support had bounced back to the levels it had enjoyed before Mr. Rudd’s popularity crashed in April.

Mr. Rudd, elected in 2007, had been one of the most popular Australian prime ministers of modern times until he made a series of policy backflips that included shelving a key promise to make major polluters pay for the carbon gas that they emit.

Many voters then abandoned Labour for the left—wing minor opposition Australian Greens party, earlier Newspolls indicated.

But with Ms. Gillard at the helm, Labour support had climbed seven percentage points to 42 percent since the previous Newspoll was conducted June 18—20. Greens support had slipped from 15 to 10 percent while the main opposition coalition remained steady at 40 percent.

The latest Newspoll, published in The Australian newspaper, is based on a random national telephone survey of 1,142 voters at the weekend and has a 3 percentage point margin of error.

Lesser known polls published at the weekend also showed the government gained popularity through the leadership change ahead of elections Ms. Gillard is due to call later this year.

Opposition leader Tony Abbott’s support as preferred prime minister plummeted eight percentage points to 29 percent between polls. Mr. Rudd’s support had been 46 percent in the previous Newspoll. Ms. Gillard improved on that with 53 percent support in the latest poll.

Newspoll chief executive Martin O’Shannessy last week predicted that Labour’s popularity would improve because all new leaders enjoy a “honeymoon” with the Australian public before voters turn against them. But new leaders’ popularity can be short lived.

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