The first representative to sponsor the bill was Minister for European Affairs and Foreign Trade Alexander Stubb, a member of the conservative National Coalition. Several other cabinet members have added their names to the list. Among party leaders, SDP chair Jutta Urpilainen, the Swedish People's Party's Stefan Wallin, the Green League's Ville Niinistö, and Paavo Arhinmäki of the Left Alliance have also given their backing to the motion.
If passed, the new legislation will give same-sex couples the right to contract a civil marriage. The bill does not include changes that affect the rights of religious communities to define marriage.
Under the terms of the proposed gender-neutral marriage act, couples will be able to take a common surname and will have the right to adopt children from outside the immediate family.
Wednesday's preliminary debate will decide whether or not the bill will be sent to Parliament's Legal Affairs Committee for review.