A fight in Congress is this week reaching a fever pitch over a change in rules that could make it easier to stop bosses who intimidate workers seeking to organize unions.

The resolution of disapproval, which on Tuesday passed a motion to proceed 53-45 along strict party lines, is likely to pass the Senate on Wednesday. Because it is being brought up under the Congressional Review Act, it is not subject to filibuster.

But whether or not the House takes up the measure appears of little consequence—the President threatened to veto the bill on Tuesday afternoon, and neither the House nor Senate seem to be able to muster the whip count needed to overturn any executive refusal to sign the politically divisive bill.

“Instead of seeking to undermine a streamlined democratic process for American workers to vote on whether or not they want to be represented, the Congress should join the President in strengthening protections for American workers and giving them more of a voice in the workplace and the economy,” the White House said

At the heart of the debate is a National Labor Relations Board ruling on “representation case procedures”–a rule change that will hasten union elections.

The rule has been in the works for years, subject to numerous courtroom battles, and, in its current form, was finalized in December. It is set to take effect on April 14.

A gaggle of leading Republicans in Congress, including Senate Majority Leader Mitch McConnell (R-Ky.) and Speaker of the House John Boehner (R-Ohio), complained in a joint Feb. 9 press release that the new NLRB regulation will cut down campaigns on certification votes to 11 days, from the current median of 38 days.

“It’s designed with one purpose in mind–to fatten the wallets of powerful political bosses by threatening the rights of middle-class workers to make informed decisions of their own,” McConnell claimed.

“The recent ambush election rule will deny workers their right to make fully informed decisions in union elections,” Boehner stated.

But advocates of the rule change say that shorter campaigns are needed for the exact opposite reason—the deck is stacked in favor of bosses wielding disinformation and both implicit and explicit threats.

“They have overwhelming resources with which to quickly mount a campaign, including anti-union ‘captive audience meetings,’ exclusive and unlimited access to employees during working hours, and the ability to have the first and last words before workers vote in NLRB elections,” John Logan, San Francisco State University professor of labor studies wrote in The Hill last year.

“Union avoidance consultants are given unlimited access to employees at the workplace and counsel employers not to wait until they face an organizing campaign before communicating their anti-union views,” he also wrote, saying the psychological assault on workers often starts “the very first day they are hired.”

Logan also said the term “ambush election” being employed by Republicans is “ludicrous.”

“Employers know a union is organizing long before it files a petition for an election, and NLRB cases are replete with examples of employer retaliation before the union files for an election,” he stated.

Although the issue seems to be getting little attention in the national press, Senators frantically took to Twitter to express what Wednesday’s expected vote means to them.

Sen. Johnny Isakson (R-Ga.) posted his statement on the resolution, calling on the Senate to disapprove of the “overreach,” while Sen. Tim Scott (R-S.C.) broadcast a photograph of himself en route “to the Senate floor to speak on the @NLRB’s dangerous #AmbushElection rule.”

Sens. Patty Murray (D-Wash.) and Dick Durbin (D-Ill.), meanwhile, praised the rule as one that would protect and grow the middle class, and Sen. Bob Casey (D-Pa.) touted Democrats’ efforts “to push back on a GOP attack against new commonsense protections.”

Sen. Chuck Schumer (D-N.Y.) published an info-graphic that, perhaps, explains best why this issue has attracted so much attention on Capitol Hill, in spite of minimal news coverage.

“The Republican plan to rig the rules in favor of special interests by delaying union elections could cost millions of hard-working Americans a shot at better pay,” the Senator’s post said. “In 2014, union members earned 27% more wages than non-union workers, with a median weekly earnings of $970 for a union member and just $763 for non-union members.”