After legalizing marijuana in 2012, it's now up to Colorado voters to put a number on the amount of taxes the state should charge for pot sales.

Citizens took to the polls on Tuesday, to weigh in on a ballot measure that symbolized the "politics of compromise," head of tax proposal Democratic Rep. Jonathan Singer told USA Today. Legislators took a long time to establish a proper proposed tax on pot - it had to be high enough to gain funds, but low enough so that consumers wouldn't run to the black market after experiencing sticker shock.

In Colorado, voters must approve any tax increase.

Voters have been presented with a 15 percent excise tax on pot growers - the proceeds will go toward school construction - along with a 10 percent special sales tax on customers to pay for marijuana law enforcement. Singer told USA Today that officials estimate pot sales could add around $67 million yearly to the state's wallet.

The bill is a flexible one, since this piece of legislation is new, uncharted territory for most U.S. states. The state legislature can up the 10 percent sales tax up to 15 percent in the next few years, but the excise tax won't go higher than 15 percent, according to the proposal. But if law enforcement officials notice that the prices are too high, driving marijuana users to purchase pot on the black market, excise and sale taxes could lower.

"The number one truth is, we don't know because no one's done this before," Singer told USA Today.

Colorado and Washington recently legalized recreational pot. They are the only states in the U.S. to have done so.

Washington established a 25 percent marijuana tax that is collected three times-growers, processors and consumers all pay up. Applications to open marijuana businesses are currently being accepted in the state.

20 states, along with the District of Columbia, currently permit the use of medical marijuana. Pot is still illegal under federal law.