Mississippi is voting on a measure that could make it the first US state to define a fertilized human egg as a person.
The measure would confer rights on an embryo from the moment of conception, effectively outlawing abortion, even in cases of rape and incest.
A survey indicates that 45% of voters in Mississippi back the measure, 44% are against, and 11% undecided.
But even if it does pass, it is not expected to withstand legal challenges.
Under the so-called personhood ballot, voters on Tuesday are being asked: “Should the term ‘person’ be defined to include every human being from the moment of fertilization, cloning, or the functional equivalent thereof?”