A last-minute addition to the Republican tax bill that could personally save President Donald Trump and several GOP congressional leaders millions was a way to “cobble together” enough votes to pass the controversial measure, Sen. John Cornyn (R-Texas) told ABC.

The new provision would allow owners of income-producing real estate to take advantage of a 20-percent deduction for money in “pass-through” entities, such as limited liability companies. The deduction would likely save the president, his family, and Republican leaders tens of millions of dollars in taxes, according to an analysis by the International Business Times. Trump and other members of Congress have stakes in several real estate-related LLCs and similar entities.

The new deduction was slipped into the tax measure Friday during the process reconciling bills from the House and Senate. Shortly after it was added, GOP swing vote Sen. Bob Corker (R-Tenn.) declared his support for the bill. The provision would boost Corker’s income through his real estate holdings, IBT reported.

Asked Sunday by George Stephanopoulos on ABC’s “This Week” why the new break was added so late in the process, Cornyn, the Senate majority whip, responded: “Well, we were working very hard. It was a very intense process ... And what we’ve tried to do is cobble together the votes we needed to get this bill passed.”

Cornyn argued that the tax measure will benefit everybody, and said it’s unfair to single out one multi-million-dollar tax break in a 1,000-page bill. He conceded that if the Democrats had participated in negotiating the measure, “we probably could have made it better.”

Cornyn dodged and switched subjects when Stephanopoulos asked: “So is that how you got Senator Corker, with this provision?”

Sen. Chris Van Hollen (D-Md.) told ABC he doesn’t know how the provision slipped into the bill. “What we do know is they’re behind closed doors,” he said. “There are a whole army of lobbyists who were surrounding them, and the longer they’re in there, the more you see these special interest provisions.” He said the provision “would be a windfall to Donald Trump based on everything we know. Of course, he hasn’t released his tax returns.”

Van Hollen said the bill, which slashes corporate taxes from 35 percent to 21 percent, and doubles estate tax exemptions for multi-millionaires, is a “total betrayal” of Trump’s “economic populist message.” People are “catching on,” added Van Hollen. “That’s why it’s so unpopular.”

Strangely, Corker sent a letter on Sunday to Senate Finance Committee Chairman Orrin Hatch (R-Utah) asking how the provision that benefits him made it into the final version of the tax-reform bill, The Hill reported.

“Because this issue has raised concerns, I would ask that you provide an explanation of the evolution of this provision and how it made it into the final conference report,” Corker wrote.

IBT previously reported that 13 GOP lawmakers wielding key power in the tax bill — including House Speaker Paul Ryan — have between $36 million and $163 million in pass-through real estate Entities, which generated between $2.6 million and $16 million in “pass through” income.

Trump made between $41 million and $68 million from 25 “pass-through” businesses he owned in 2016, while Corker earned between $1.2 million and $7 million in rental income from his companies last year, IBT reported.

The bill is expected to be voted on this week.