Supporters and opponents knew Amendment 2 will be called the "gay marriage amendment," but neither see it that way. They also agree that the vote will be close, but that's about it.
Amendment 2 would do one thing, supporters say -- define marriage as between a man and a woman in the state constitution. Opponents argue that the amendment is unnecessary because there is already a state law banning same-sex marriage and that its vague wording would create unintented consequences for gay and straight couples.
Amendment 2 is the only citizen-sponsored amendment on Tuesday's ballot; the others were placed by the Legislature and a tax commission. Like the other amendments, it needs 60 percent support to pass.
Florida is one of more than 40 states with laws defining marriage as the union of one man and one woman, but that isn't sufficient. Supporters of Amendment 2 want Florida to join 27 other states that specifically define marriage in their consitutions. That would help prevent court rulings allowing same-sex marriage like those in Massachusetts, California and, recently, Connecticut.
Some opponents say the amendment is a way to get conservative voters to the polls for Republican presidential candidate John McCain, but supporters say they simply want to preserve marriage as it's currently defined.
Opponents argue that the amendment's vague wording would create problems for some unmarried couples, potentially stripping them of health care and other benefits.
They say more than 10,000 couples have signed up on domestic partnership registries created by cities or counties statewide. Those registries give same-sex couples and heterosexual couples rights like being able to see each other in hospitals.
Some elderly couples register as domestic partners because if they marry they would lose Social Security or other benefits from a deceased or divorced spouse.
But supporters say even if domestic partnerships were eliminated -- and they don't think that would happen -- that wouldn't prohibit a private company from extending benefits to whoever they wish.
Mathew Staver, the founder and president of Liberty Counsel, a conservative Christian legal group, helped draft both Amendment 2 and the 1997 Florida Defense of Marriage Act.
Staver and other proponents say domestic partnerships wouldn't be affected by Amendment 2. Domestic partnerships aren't "treated as marriage" or the "substantial equivalent" of marriage described in the amendment.
Opponents say if the amendment passes a court would ultimately have to decide whether domestic partnerships are "treated as marriage" or the "substantial equivalent" of marriage and therefore banned.