Amid mounting criticism over the perceived unfair constraints imposed by the U.S. Securities and Exchange Commission's Staff Accounting Bulletin 121 (SAB 121), a House proposal aimed at overturning the controversial rule is anticipated to navigate through the Senate with favorable prospects, according to sources familiar with the matter who spoke to CoinDesk.

Insiders familiar with Senate proceedings revealed to CoinDesk the likelihood of a floor vote scheduled for Thursday morning, expressing confidence in the bill's favorable stance for approval.

"There'll likely be more than one Democrat voting for it," remarked one individual privy to the Senate deliberations.

SAB 121 was introduced with the aim of providing clarity on the accounting treatment of crypto assets, stipulating that businesses should reflect these assets on their balance sheets. However, critics contend that the bulletin creates undue hurdles for major custodians and corporations, dissuading them from offering crypto custodial services to clients altogether. Last week, the House of Representatives took a significant step forward by advancing a resolution rejecting the guidance.

Should the House resolution receive the green light from the Senate and ultimately be signed into law by U.S. President Joe Biden, it would signify a disapproval of the bulletin while precluding the SEC from issuing similar guidance in the future. Despite a warning from the White House threatening a potential veto, citing the bulletin as a reflection of "considered SEC staff views" and cautioning against constraints on the agency's regulatory authority pertaining to crypto-assets, the resolution garnered bipartisan support in the House.

In a statement, Rep. Mike Flood (R-Neb.), the resolution's sponsor, expressed optimism about its prospects, emphasizing the seriousness with which Congress views the matter.

"We're hopeful that it passes the Senate this week, and I think it's getting the SEC's attention that we're serious," remarked Flood.

Ron Hammond, director of government relations at the Blockchain Association, echoed expectations of bipartisan backing for the resolution while urging a reconsideration of the veto threat, citing the adverse impact of the "anti-crypto provision" contained within the bulletin.

"However, the threat of a presidential veto remains," cautioned Hammond. "We encourage the veto to be reconsidered, allowing this harmful, anti-crypto provision to be struck down."