Polls have closed in Finland's parliamentary elections, with early, unofficial results showing conservatives holding a slim lead over opposition Democrats and a surging nationalist party that wants to block bailouts for debt-ridden Portugal and other financially-troubled eurozone members.

With about one-third of the votes tallied just minutes after polls closed, YLE national television showed the National coalition party - part of the current center-right government - with 20 percent of the votes.  Opposition Democrats were carrying 19.4 percent and the nationalist, anti-immigration True Finn party nearly 19 percent.

The rise of the True Finns' has led to worries about whether eurozone economies can depend on Finland's support for bailout funds, which must be unanimously approved by the 17 countries using the Euro.

Observers reported a high voter turnout that some analysts say would approach 70 percent.

Full results are expected late Sunday.