House Republicans opposed to ending the federal tax deduction for state and local taxes are under pressure from a political group supportive of President Trump.

The House Republican plan to overhaul the federal tax code includes a proposal to nix a popular deduction for state and local taxes, and some Republicans from high-tax blue states are balking, arguing it would amount to a tax hike on their constituents.

To build pressure on these Republicans to get on board, 45Committee — a political nonprofit that backs Trump's agenda — is going on television and radio this week with television ads urging nine of them to support the legislation.

“45Committee is committed to passing tax cuts that deliver for America’s working families. Elected officials of both parties and in both houses of Congress have made a commitment to lower taxes on middle class families," Brian Baker, chairman and president of 45Committee, said in a statement.

"These advertisements communicate that constituents are counting on their elected representatives to follow through on tax reform so that America’s families win, while also giving a boost to our nation’s economy.”

With Democrats expected to unanimously oppose the Tax Cuts and Jobs Act, House Republicans cannot afford to lose too many votes and still pass the bill, especially given the ambitious plans to send the legislation to the Senate for consideration before Thanksgiving.

The ads from 45Committee, part of a planned $10 million to help Trump enact tax reform, are individualized for each of the nine members it is targeting, and aim to help the administration and Republican leaders overcome internal opposition. Trump is a major proponent of ending the federal deduction for state and local taxes, referred to in Washington as the "SALT" deduction.

Republican members targeted in this round of ads include: New York Reps. Lee Zeldin, Claudia Tenney, John Faso, and Dan Donovan; New Jersey Reps. Chris Smith and Leonard Lance; California Reps. Darrell Issa, Jeff Denham and Steve Knight. Additional members are being targeted with digital spots.

The spots open with an announcer saying the congressman or woman targeted in the ad was "elected to cut taxes," and ends with the announcer saying: "Keep your promise and vote yes on tax reform."