The Chamber will consider the vote "in our annual How They Voted scorecard," R. Bruce Josten, executive vice president for Government Affairs, wrote in an open letter to lawmakers.

"With more than eight million Americans unemployed, Congress should reject attempts to instigate a debate on class warfare and focus on real initiatives that can get the American economy further down the road to recovery," Josten wrote. "Raising taxes on higher earning taxpayers would hurt business owners on whom our economy depends to create jobs."

Republicans have repeatedly criticized Democrats' push of the Buffett Rule, calling it just a political stunt. If it passes the Senate, it will likely be voted down in the GOP-controlled House.

Since Monday night's vote is a procedural vote for cloture, at least some Republicans will be needed in order to reach the 60 votes necessary to move the legislation forward. Given the GOP opposition, however, the vote is expected to fail, thereby killing the measure.

Instead of the Buffett Rule, the Chamber urges Congress to extend existing tax cuts.

"Rather than legislation, such as S. 2230, that smacks of political gimmickry, the Chamber urges the Senate to avoid the class warfare rhetoric and, instead, extend expiring and expired tax provisions and the 2001/2003 tax rates for all taxpayers while working towards comprehensive tax reform," Josten adds in the letter.

Ahead of the Monday evening procedural vote, Sen. Charles SchumerCharles (Chuck) Ellis SchumerOvernight Finance: Trump signs repeal of auto-loan policy | Justices uphold contracts that bar employee class-action suits | US, China trade war 'on hold' Free traders applaud Trump as China tariff threat recedes The Hill's 12:30 Report — Sponsored by Delta Air Lines — Frenzy over Kennedy retirement rumors | Trump challenges DOJ MORE (N.Y.), the top messaging Democrat in his chamber, said that Democrats are hoping to gain some Republican votes on the Buffett Rule but would continue to push the legislation even without GOP support.

"We hope to pick up some Republicans in the vote today but even if we come up short of the votes needed, we'll keep on pushing this all year long," Schumer said on a conference call with reporters.