A gay marriage bill approved by Argentina's Chamber of Deputies (la Camara de Diputados) faces a tight vote in the Senate.

In a poll conducted by news agency DyN released Thursday, 27 senators said they are in support of the bill, while another 27 said they would vote against it. One senator said he will abstain.

That only leaves 17 lawmakers unaccounted for.

Argentine President Christina Fernandez de Kirchner has said she would not block the measure from becoming law, if approved by senators.

But even the president's own political block, the Front for Victory, which is behind the bill, is divided on the issue. Of its 32 senators, only 14 said they planned to vote for the bill.

The bill has been assigned to the General Law Committee chaired by Liliana Negre de Alonso, who has said that while she disagrees with giving gay and lesbian couples the right to marry, she won't block debate on the issue.

Senators are not expected to vote on the bill until July, at the earliest.

The gay marriage bill advanced in the Chamber of Deputies along a 125-to-109 vote after lawmakers debated between moving on a bill that would give gay and lesbian couples the right to marry – including the right to adopt – and a civil unions bill that did not include gay adoption.

Gay marriage has dominated national headlines since December when two men married for the first time in Latin America. Just days before deputies debated the measure, two men in Buenos Aires became the fifth gay couple to marry in Argentina.

The Roman Catholic Church is strongly opposed to the legislation.