The figure represents a fall of 1.3 percentage points on the previous Skop survey.
The coalition has been hit recently by a series of revelations surrounding party members’ and state secretaries’ failure to pay tax on household services such as cleaning and nannying.
The poll shows support for the three opposition parties has edged 1.1 percentage points higher, to stand at 51.7 percent.
The main opposition party, the Social Democrats, has extended its lead to over 39 percent, the party’s highest showing in a Skop survey since general elections in September last year.
A separate poll, carried out by the Sifo market research agency, shows voters’ faith in Swedish Prime Minister Fredrik Reinfeldt has been hit, with over 40 percent saying their trust in Reinfeldt has been undermined in recent weeks.