The anti-euro True Finns party has won 18.6% of postal votes in the Finnish general election - a higher figure than expected.
The True Finns only secured 4% of the vote in 2007, but the postal ballot suggests the party could exceed the projected quadrupling of its support.
Finland is the only euro-zone state which requires any bail-out to be passed by a parliamentary vote - something which had raised concerns that an anti-euro Coalition in Finland could hold-up the expected bail-out of Portugal.
However, analysts say the centre right National Coalition party has secured more than 20% of postal ballots, and this reduces the chances that Portugal's bail-out could be disrupted.
Results of the election should be known later tonight.
The reason the outcome of this election is being watched so closely is that Finland's parliament has the right to vote on EU bailouts, such as the one currently being negotiated between Portugal and EU and IMF officials.
And as EU rules state that any bailout must be approved unanimously by all 17 eurozone members, an anti-euro Finnish Government could hold-up the process and further spook debt markets.
With a coalition the most likely outcome of the election, analysts say it is possible the True Finns could form part of the next government, if its MPs are prepared to tone down the anti-euro rhetoric.
What most agree is that Finland's next government will be more conservative and less European-focused, which would be a further complication in an already complicated financial situation.