Stateline looked at some of the most consequential or controversial issues on the ballot this fall.

Washington State: Genetically Modified Foods

One of the more expensive ballot fights is in Washington, where supporters and opponents have poured almost $24 million into a campaign over whether genetically modified foods, known as GMOs, should have to be labeled.

State campaign finance records this week showed contributions totaling nearly $24 million, surpassing the amount raised during the state's 2012 same-sex marriage campaign and making it the second most expensive ballot question campaign ever.

The Washington debate is similar to the fight that played out in California last year, when voters rejected a similar measure that was fiercely opposed by agricultural and food-business interests and backed by environmentalists and other liberal groups.

"It's really a proxy battle over genetically modified food, generally," said Mark A. Smith, a political science professor at the University of Washington. Those opposing the labeling often see the proposals as a watershed: If one state adopts them, the theory goes, more will follow.

With that in mind, the opposition is mobilized. More than two-thirds — $17.2 million — of the total raised is for the opposition. But supporters have millions as well.

The outcome could hinge on turnout. In much of the state – including more conservative rural areas – there are few if any high-profile matters on the ballot to draw people to the polls. But in liberal Seattle, residents will also decide a closely contested mayoral race, which could boost turnout for those who support labeling.

Colorado: Taxes in the Balance

A pair of tax measures — one levying taxes on newly legal marijuana, the other altering the state’s income tax system to support education — could make history in Colorado.

On marijuana, the question is whether the state should tax marijuana sales in two different ways, potentially bringing in a windfall of revenue but also driving up the cost of the drug. Opponents call it the biggest tax increase in state history.

The first $40 million from a 15 percent tax on the wholesale price of retail marijuana would go toward education. The second 10 percent sales tax would be in addition to the state’s 2.9 percent sales tax, with proceeds earmarked for regulation, public health and police activities related to the legal pot market. Of those revenues, 15 percent would go back to the cities and counties where the sales occur.

A vocal campaign against the higher marijuana taxes has taken shape in the state, with some arguing it unfairly targets marijuana users. Others say taxing too much will just drive the business back underground. Supporters say the new taxes are necessary to fund the regulation of the new market.

The second tax measure would replace the state’s flat income tax system with two tiers, with the proceeds earmarked for education. It would collect nearly $1 billion, according to state estimates. It would also require 43 percent of all state tax revenue to go toward education.