It's crunch time for cryptocurrencies.

The Senate will vote on the Clarity Act, a key bill for crypto regulation, on Tuesday afternoon.

Bitcoin and crypto-exposed stocks were falling ahead of the vote, though, after enjoying a rally in recent months as the legislation's chances of being passed have come back from the dead.

Circle fell 8%, Coinbase, BitMine fell 6%, Strategy and Bullish fell 5%, Robinhood fell 4%.

It's still a tight call. GOP senators have been making an 11th-hour push to get support from Democrats, Barron's reported Monday. But the odds of the bill passing this year slipped to 19% Tuesday from 31% yesterday, according to prediction market Polymarket. Polymarket has a data sharing partnership with Dow Jones, the publisher of Barron's.

That move, and broader pre-vote nerves are being reflected in crypto markets. Bitcoin fell to $76,900 early in the day, down 1% over the past 24 hours, according to CoinDesk data. The world's largest cryptocurrency is up 31% since the start of July but remains 12% down in 2026.

Ethereum, the second largest crypto, slipped 1.2% to $2,475, while popular altcoin XRP edged 0.5% higher to $1.40.

Cathie Wood's ARK Invest took the opportunity to sell crypto-related stocks Monday, according to a trading notification. ARK's funds sold shares in CoinDesk owner Bullish, crypto exchange Coinbase, stablecoin issuer Circle Internet Group, and Ethereum treasury company Bitmine Immersion Technologies.

Coinbase stock was down 4.5% in premarket trading, after rallying 9% in the previous session. Strategy, the largest corporate holder of Bitcoin, was down 3.7% after a 4.6% rise Monday.