A government-run opinion poll says Spain's ruling conservatives will win the most votes in Dec. 20 general elections but indicates they will likely need outside support to stay in power.

The CIS survey released Thursday said the Popular Party would win 29.1 percent of the vote, against 25.3 percent for the leading opposition Socialist party.

The centrist newcomer Ciudadanos (Citizens) party would garner 14.7 percent while the radical leftist Podemos (We Can) party would obtain 10.8 percent of the vote.

The CIS said the poll had a margin of error of 2 percentage points. It said 2,493 people were quizzed in person Oct. 1-12 for the survey.

The Popular Party won an absolute majority of seats on garnering 45 percent of the vote in 2011.