A pro-Trump outside group is taking to the airwaves in Oklahoma, pushing to make sure that GOP Sen. James Lankford votes in favor of the Senate’s tax overhaul.

Lankford has been among the Republican senators working on a so-called “trigger” option that could provide a backstop, rolling back some of the tax cuts in the event economic growth targets and thus the accompanying revenue are not met.

“I am on board with this bill because I want to see the good economic growth that’s coming with it, but I also want to make sure we’re protecting future taxpayers with debt and deficit,” Lankford said Tuesday morning on CBS.

The “Stand With Trump” ad from the 45Committee is slated to run on broadcast outlets in both Tulsa and Oklahoma City, as well as radio and local cable TV throughout Oklahoma.

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“This is your chance to cut taxes, Senator Lankford. Don’t let us down,” the ad says. “Stand with President Trump. Vote yes on tax reform.”

The spot, the script for which was provided first to Roll Call, also features a clip of Trump himself.

 The Oklahoma ad campaign pressuring Lankford is part of the 45Committee’s previously-announced eight-figure ad buy to push the tax code overhaul, which has been Trump’s top legislative priority of the fall.

Details of the trigger framework have not been made public, but under one version discussed Tuesday, up to $350 billion in automatic tax increases would kick in in 2022.

Based on a White House proposal, the trigger would provide for either an increase in the corporate tax rate or a 20 percent tax on the difference between a company’s “book” income — pre-tax income reported on financial statements — and taxable income, or possibly both types of tax increases, if revenue falls short of expectations.

Applying the corporate tax to book income means companies would lose the benefit of deductions that reduce taxable income reported to the IRS below pre-tax income reported to shareholders on financial statements

The trigger would kick in after 100 percent capital expensing, which would expire after 2022 in the Senate plan, has been in place for several years.

Many Republicans believe full and immediate expensing will jump start economic growth to the point where the automatic tax increases won’t take effect.

— Paul M. Krawzak contributed to this report.