The dreams of crypto enthusiasts inched closer to reality in recent days as lawmakers in Wyoming and Arizona put forward proposals that would allow those states to accept tax payments in the form of digital currencies.

The new proposals, and others like them around the United States, threaten to erode a key distinction upholding the supremacy of the U.S. dollar over its would-be digital competitors: Americans can use U.S. dollars, but not cryptocurrencies, to pay their taxes.

Under the Arizona proposal, the state would recognize the most popular cryptocurrency, Bitcoin, as legal tender. The Wyoming proposal, which is not limited to any specific cryptocurrency, would apply only to sales and use taxes.

Both proposals face potential legal and political hurdles. But Wyoming has gone further than any other state in passing laws to accommodate cryptocurrency adoption, and backers of the proposal there believe it will be the first state to take a significant step in the realm of tax payments.