(Bloomberg) -- New Zealand Prime Minister Jacinda Ardern extended her lead ahead of an election in September after the main opposition National Party changed its leader for the second time in two months, a new poll shows.

Ardern’s Labour Party was on 53% in a 1News/Colmar Brunton poll published Thursday in Wellington, up from 50% in the same survey just over a month ago. National was on 32%, down from 38%. The election will be held Sept. 19.

Ardern’s chances of winning a second term are being boosted by her handling of the Covid-19 pandemic and signs the economy is recovering faster than expected from lockdown. By contrast, National has spent the past month beset by scandals. In early July, a junior caucus member quit after leaking private medical records of Covid patients, and just weeks later a second backbencher resigned for allegedly sending pornographic images to young women.

The party was forced to change leaders when Todd Muller stepped down after just 53 days in the role, electing Judith Collins less than 10 weeks before the vote. Collins got 20% backing as preferred prime minister, compared to Ardern’s 54%.

If today’s poll results were replicated on election night, Ardern’s party could govern alone. That is an unlikely outcome in New Zealand’s proportional representation electoral system, which lends itself to coalition governments.

Labour’s current coalition partner New Zealand First was on 2%, well below the 5% required to return to parliament. However, its ally the Green Party was on 5%, giving the center-left a decent margin over the center-right. In a surprise, the libertarian ACT Party -- a partner for National -- saw its support rise to 5%.

The poll was conducted July 25-29 and had a margin of error of 3.1%.

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