Former House Speaker Newt Gingrich (R-Ga.) said on "America's Newsroom" that Republicans will be in real danger of losing the House in 2018 if they fail on tax cuts. 

Gingrich advised President Trump to avoid "angry rhetoric" at his rally in Phoenix tonight and not to go after the state's Republican senators, John McCain and Jeff Flake.

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"He's going to need both of them this fall [to pass] the agenda," he explained, adding that ultimately the president does and says what he wants at these campaign events.

"When the audience starts reacting and he gets excited, who knows what's going to happen."

He said Republicans must come together on a "simple" plan that cuts taxes for the middle class and small businesses and reduces the corporate rate to 15%.  

If they fail, as they did on replacing ObamaCare, he warned that Nancy Pelosi could become Speaker of the House again in 2018, leading a Democrat majority. 

Gingrich said the tax cuts must be passed before Thanksgiving and signed by President Trump in order to impact the U.S. economy in the first and second quarters of 2018.

"I'm afraid that the guys who failed to repeal ObamaCare are about to go through exactly the same dance, reassuring us right up to the failure," he concluded.

Watch the speaker's thoughts above.

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