After hitting record high support levels in April, the National Coalition Party (NCP) saw its support dip by two percentage points in Yle's latest monthly voter survey.
Tuomo Turja, Research Director at polling firm Taloustutkimus, told Yle he believed this decline in peak readings is a natural development, especially now that most other parties have clarified their positions on Nato membership.
"In the March survey, NCP's positive Nato position was a factor that increased the party's support. It may be that support for NCP still reflects the party's pro-Nato stance," Turja told Yle.
The NCP has historically been the party most in favour of Nato membership and it has been a longstanding party position, which has credited them with their boost in the polls as more and more Finns support the submitting of an application to join the alliance.
As other parties have started adopting pro-Nato positions, this will most likely bring NCP's support back down, which has already been observed at a small scale in the latest poll.
Turja pointed out that the NCP has been able to hold onto their own voters, whereas those who voted for the Centre, Finns, Christian Democrats, and Swedish People's Party (SPP) in previous elections increasingly said they no longer support NCP in the most recent poll.
"It can be said that the NCP received an exceptional amount of extra support from other parties in the previous poll," Turja emphasised.
The Social Democratic Party (SDP) was the second most popular party in the poll, but has lost one percentage point of support since the previous poll.
"SDP lost some supporters to the Left Alliance," Turja noted, adding that support for the party of Prime Minister Sanna Marin has been relatively steady over the past few polls.
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Left overtake Greens
Support for the nationalist Finns Party grew by one percentage point compared to Yle's last poll, while the Centre Party also saw similar gains., Both parties owed this bump to their adoption of pro-Nato stances as well as gaining support from NCP's small drop.
The latest also showed a rare changing of positions, as the Left Alliance gained more support than their governing coalition partners the Greens. Both parties did not have large changes in support, but Turja noted that this was a symbolically significant issue for both parties.
"It is certainly not common for the Left Alliance to surpass the Greens. If I looked right, the last time support of the Left Alliance had been slightly higher than Greens was in October 2014," Turja mentioned.
Support for smaller parties remained steady in this poll, with the SPP, the Christian Democrats and Movement Now all staying at similar levels.
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