The world’s largest cryptocurrency by market capitalization continued to push past year-long highs, as Bitcoin approached $38,000 late November 9 morning, an approximately 7% increase in the past 24 hours, according to data from CoinGecko. Its peak of $37,935 was the highest the coin has reached in more than 18 months.

Ether, the token for the Ethereum blockchain and second-largest cryptocurrency by market capitalization, was also up, crossing the $2,000 mark for the first time since July on the back of an 8% day-over-day price upswing.

The market capitalization for all cryptocurrencies increased approximately 5.4% day-over-day to $1.45 trillion, as some of the other largest coins on the market saw large gains as of November 9 morning, including Cardano (8.2%), Solana (9.9%), and Chainlink (12.7%). The movements in the crypto markets far outpaced the stock indices, with the NASDAQ and S&P 500 basically flat over the past 24 hours.

Bitcoin’s recent upswing is mainly due to “optimism around a near-term spot Bitcoin ETF approval and a resulting short-squeeze,” Brian Rudick, a senior strategist at crypto trading firm GSR, told Fortune, referring to a Bitcoin-based financial product that traditional investors can trade. And on November 9 morning, BlackRock registered the name “iShares Ethereum Trust” in Delaware, an indication “that it is likely to file a spot ether ETF application soon,” he added.

David Lawant, head of research at crypto brokerage and trading platform FalconX, echoed Rudick’s assessment. Bitcoin “continues to perform well as the market focuses on the U.S. spot ETF approval process,” he told Fortune, adding that the “big star of the day” has been Ethereum, following news of BlackRock’s registration of the “iShares Ethereum Trust” name.

The rapid rise in the prices of major cryptocurrencies continues a month-long rally in the digital assets market. The total market capitalization for all cryptocurrencies has rocketed about 30% since Oct. 9, rising alongside optimism over the likely approval of a spot Bitcoin ETF, or exchange-traded fund.

Traditional investors, who manage trillions of dollars in capital, are largely constrained by the investment products available on portfolio management platforms like Vanguard or TD Ameritrade. If the Securities and Exchange Commission were to approve a spot Bitcoin ETF, which lets traditional investors trade on current Bitcoin prices, crypto industry boosters are betting that tremendous amounts of capital would flow into the Bitcoin—and crypto—markets.

While the industry has repeatedly tried and failed to convince the SEC to approve a spot Bitcoin ETF, BlackRock, the largest asset manager in the world, filed an application for its own spot Bitcoin ETF in June. Since then, the crypto markets have rallied, and other financial institutions have filed their own ETF applications, hoping to cash in if the SEC were to approve the application from BlackRock, which has a sterling record of past ETF approvals.

And starting November 9, a brief period for the SEC to approve a spot Bitcoin ETF opened, according to Bloomberg Intelligence analysts, who believe that, even if approvals don't come in November, there is a 90% chance of approval by January.

"There is significant hype surrounding the recent comments from Bloomberg regarding the ETF 'window,'" James Butterfill, head of research at CoinShares, told Fortune. "Admittedly, it is always a little worrying when prices rise so sharply. That said, as we enter into this new bull market, it is worth reflecting on the point that we remain well below the all-time-highs seen in 2021."