Any of three states Maine, Maryland and Washington could become the first to legalize same-sex marriage through a popular vote, a potentially momentous development that could influence future Supreme Court deliberations on the issue. Thus far, all 32 states with referendums on gay marriage have rebuffed it, while the six states that have legalized it did so through legislation or court orders.
Washington is in another three-state group, with Oregon and Colorado, that could become the first to legalize recreational use of marijuana allowing adults to possess small amounts of pot under a regimen of state regulation and taxation. The Oregon proposal appears to be fizzling, but the Washington and Colorado measures have led in opinion polls and are backed by wealthy out-of-state donors.
A "yes" vote in any of the states could set up a showdown with the federal government, which continues to consider pot an illegal drug. The Justice Department has declined to elaborate on how it would react.
Two other states Arkansas and Massachusetts will be deciding whether to allow marijuana use for medical reasons, as 17 states have done previously. Arkansas would be the first Southern state to join the group.
Another emotionally charged measure in Massachusetts would legalize physician-assisted suicide. Massachusetts would join Oregon and Washington in allowing terminally ill patients to obtain lethal doses of medication if doctors say they have six months or less to live.
The measure raises "the most profound questions that an individual can wrestle with," said the Rev. Tim Kutzmark, of Reading, Mass., a Unitarian Universalist minister who shifted from a foe of assisted suicide to a supporter after watching a close friend slowly die from Parkinson's disease in 2002.
As is often the case, California has numerous attention-getting measures, including one that would abolish the state's death penalty. If approved, the more than 720 inmates on California's death row would have their sentences converted to life in prison without the possibility of parole.
While 17 states have ended capital punishment, most did so through legislative action. Only in Oregon, in 1964, did voters choose to repeal the death penalty, and they later reversed themselves to reinstate it.
Another contentious measure in California would require most genetically engineered processed foods and produce sold in supermarkets and other outlets to be labeled as such. These GMO foods also will be prohibited from carrying the term "natural" on their labels.
Consumer groups and the organic food industry support the measure as a way of giving shoppers more information about what they purchase and consume, while many retailers are opposed, saying grocery bills would increase. Food and chemical conglomerates, including Monsanto Co. and DuPont Co., have contributed nearly $41 million to defeat the measure close to 10 times what its supporters have raised.
California's epic budget problems also are on the ballot, in the form of rival tax-increase proposals.
Democratic Gov. Jerry Brown's Proposition 30, aimed at averting $6 billion in budget cuts, mostly to education, would raise income taxes on people who make more than $250,000 a year for seven years and raise the state sales tax by a quarter cent for four years. Proposition 38, sponsored by wealthy civil rights attorney Molly Munger, would raise income taxes on nearly all earners and send the money directly to local school districts, bypassing the Legislature.
California labor unions are the target of another measure, aimed at depriving them of tens of millions of dollars they use to finance campaigns and political organizing.
Proposition 32 would prohibit corporations and unions from collecting money for state political activities from employees or members through paycheck deductions. It would hit unions hardest: Corporations don't typically deduct money from employee pay for state political activities, but unions do use the practice to fill their political coffers.
The battle over Proposition 32 follows conflicts in Wisconsin, Ohio, Indiana and elsewhere where Republican efforts to weaken organized labor have produced protests and political tumult.
In Michigan, labor unions are fighting back. On Nov. 6, voters there will be deciding on a first-of-its-kind ballot initiative that would put collective bargaining rights in the state constitution and out of lawmakers' reach.
If successful, the strategy could serve as a model for other states, encouraging unions to bypass hostile officeholders and take their case directly to voters.
"Labor is on the defensive," said Lawrence Mishel, president of the Economic Policy Institute, a liberal research organization in Washington, D.C. "This could very well be a turning point if the people of Michigan affirm collective bargaining."
Other notable ballot measures:
• In Alabama, Montana, Florida and Wyoming, voters have an opportunity to weigh in on one key aspect of President Barack Obama's health care overhaul in the form of Republican-backed measures stating that no individual or business can be compelled to participate in a health care system. The measures are viewed as largely symbolic; they would violate federal law and any attempt to enforce them would likely wind up in the courts.
• Maryland voters will decide whether to uphold or overturn a new state law allowing illegal immigrants to pay in-state tuition at public colleges if their parents have paid taxes and if the students have attended Maryland schools.
• Illegal immigrants are the target of a measure in Montana, placed on the ballot by lawmakers, that would require people who receive certain state services to provide proof of U.S. citizenship or legal residency.
• A measure in Ohio would create a 12-person citizen commission to draw up legislative and congressional districts, taking that power away from legislators.
• Oklahoma voters will decide whether to abolish affirmative action programs in state government and education. That's a step already taken in Arizona, California, Michigan, Nebraska and Washington.
• Minnesotans will decide on an amendment that would require showing a photo ID in order to vote.
• A proposal in Missouri would raise the state cigarette tax to 90 cents per pack, up from a lowest-in-the-nation 17 cents per pack.