(Bloomberg) -- Denmark’s Prime Minister Lars Lokke Rasmussen is catching up on his main political opponent, Mette Frederiksen of the Social Democrats, according to an opinion poll measuring credibility.

About 20 percent of the voters say Lokke Rasmussen is the most credible politician of the two, compared with 35 percent for Frederiksen, according to the Greens survey published by newspaper Borsen on Monday. In September 2015, 58 percent said Frederiksen was the most credible while 19 percent said Lokke Rasmussen, according to the Copenhagen-based newspaper.

Lokke Rasmussen’s center-right government can call elections at any time but must due so no later than June 2019.

The margin of error in the the survey, which included 1,131 interviews in the period July 27 to Aug. 2, was 1.9-2.8 percentage points, Borsen said.

To contact the reporter on this story: Christian Wienberg in Copenhagen at cwienberg@bloomberg.net

To contact the editor responsible for this story: Tasneem Hanfi Brögger at tbrogger@bloomberg.net

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