Updated

Voters in New Mexico's largest city will decide Tuesday whether to ban late-term abortions.

The municipal referendum is believed to be the first of its kind in the country and is being watched as a possible new front for activism in the abortion wars that have typically been waged at the federal and state levels.

The outcome is anyone's guess following an emotional and graphic campaign that brought in national groups and hundreds of thousands of dollars on advertising.

More early voters turned out than in last month's mayoral election, but there has been no polling and the city clerk has not released information on voters' party affiliation.

If the referendum passes, a legal challenge is expected. Attorney General Gary King, a Democrat, has said he believes the law is unconstitutional.

The issue was put to voters after former Operation Rescue interns and anti-abortion "missionaries" Tara and Bud Shaver moved here with the goal of shuttering Southwestern Women's Options, one of just a handful of clinics in the country that perform late-term abortions.

Tara Shaver says her group, Project Defending Life, gathered signatures to get the measure on the city ballot after failing to make headway in the Democratic-controlled Legislature.

NARAL Pro-Choice America President America Ilyse Hogue said that it is the first municipal ballot on abortion that she knows of and that her group is watching the election closely.

Asked if other cities with late-term abortion clinics might be targeted in the future, Shaver said, "We are encouraging people to see what can be done at the city level. ... We are starting to get calls from people asking us how to do what we have done."

Polls close at 7 p.m. Mountain time.

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