Sifo figures confirmed for the third consecutive poll that the Christian Democrats would achieve the four percent support required to claim seats in parliament while the far-right Sweden Democrats would be excluded from parliament.
The gulf between Sweden's two largest parties, the Moderates and the Social Democrats, has shrunk to four points with the parties claiming 30.6 percent and 34.6 percent respectively.
The figures for the smaller parties were as follows with the change on Sifo's March poll in brackets:
Left party 5.3 percent (-0.2 percentage points), Green party 8.6 (+2.0), Centre party 5.8 percent (-0.5), Liberals 6.8 (+1.2), Christian Democrats 4.1 (+0.8), Sweden Democrats 2.8 (+0.2) and other parties 1.5 (+0.1).
Only the change in the figure for the Green party is statistically significant, all other figures are within the margin of error.
Sifo interviewed 1,914 Swedish voters between April 6th - April 16th. The results were published in Svenska Dagbladet and several other dailies on Sunday.
In addition Sifo also surveyed voter sympathies in big city areas and found that the Alliance coalition commanded a 13 percentage point lead in Stockholm and 9.7 points in Gothenburg, while in Malmö the opposition retained a five point lead.
Polls from Demoskop and Skop conducted two weeks ago showed that the Alliance coalition had overtaken the opposition and a new Skop poll published on Sunday confirmed the trend.
In the Skop poll the four party Alliance claimed a combined 50.6 percent voter support while the opposition had 45.5 percent, a decline of 0.7 percentage points.
The Social Democrats remain the largest political party in Sweden, with 33.8 percent while the Moderates claimed 33.2 percent of voter sympathies.
Skop conducted its poll from April 1st to April 18th.
Both the Sifo and Skop polls confirm that the Social Democrats are running below the historically low level of support gained in the 2006 election.
"This is the closest situation in Sifo between the blocs since the opposition overtook the lead in November 2006," political scientist and researcher Sören Holmberg told Svenska Dagbladet.