The poll showed 52 percent of respondents supported the Southwest Finland MP Virta for the position.
However, according to MTV, roughly one in four respondents were not yet able to say who they supported.
The new chair of the Green Party will be elected later this week at the party's meeting in Seinäjoki.
Second-term members of parliament Virta and Saara Hyrkkö (Green) are both vying for the seat. Maria Ohisalo (Green) announced that she was stepping down from the role after the party lost seven seats in April's parliamentary elections.
MTV Uutinen's survey was answered by 65 people, correlating to a response rate of 59 percent by the delegates.
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