The latest opinion survey conducted by United Minds and Cints in collaboration with newspaper Aftonbladet shows that both the ruling Moderates and Liberal Party have increased their levels of support.
Separately, support for the Centre and Christian Democratic Parties has fallen below the levels they registered for the general election on September 19th. However, the Christian Democrats, the smallest party in the Riksdag, would clear the 4 percent threshhold to remain in parliament.
Meanwhile, the Social Democrats continue to lose support from voters.
"If it were close to an election, it would be more problematic, but I think people understand that there is not an election now and that much can happen," United Minds' opinion director Carl Melin told Aftonbladet.
While support for the Social Democrats and Left Party continue to fall, the Green Party continues to gain more support. Support for the far-right Sweden Democrats also outpaces the party's election result in the fall.
The Moderates currently have 31.7 percent support, up 0.7 percentage points from November. The Liberal Party stands at 7.5 percent, 0.5 percentage points ahead of last month.
However, the Centre Party and Christian Democrats are at 5.5 percent and 4.8 respectively, down 0.8 and 0.1 percentage points respectively.
Together, the Alliance has 49.5 percent, up 0.3 percentage points from November, compared with 42.2 percent for the Red-Green parties, whose support fell 1.2 percentage points.
Among then, support for the Social Democrats slipped 1.5 percentage points to 27.6 percent and 0.6 percentage points to 5.2 percent for the Left Party.
However, backing for the Green Party grew 0.9 percentage points in December to 9.4 percent from the previous month. Support for the Sweden Democrats also rose 0.9 percentage points to 6.9 percent this month.
Support for other parties increased 0.1 percentage points to 1.4 percent.
United Minds interviewed 1,148 respondents over the age of 18 from November 23rd to Sunday, asking them, "How would you vote if there were a Riksdag election today?"