Story highlights The speech comes hours after Trump suffered a stinging defeat in Alabama

House and Senate negotiators struck a tentative deal on the tax bill Wednesday

Washington (CNN) President Donald Trump, eyeing his first major legislative victory, made his closing argument Wednesday on a tax package that negotiators on Capitol Hill are "days away" from passing.

"As a candidate, I promised we would pass a massive tax cut for the everyday working American families who are the backbone and the heartbeat of our country," he said. "Now, we are just days away, I hope, I hope, you know what that means, right, from keeping that promise and delivering a truly amazing victory for American families."

He added: "We want to give you, the American people, a giant tax cut for Christmas. And when I say giant, I mean giant."

The speech comes hours after Trump suffered a stinging defeat in Alabama, where Democrat Doug Jones defeated Republican Roy Moore to unexpectedly win a Senate seat in a deep-red state. The loss, which shrinks Republican control of the Senate to a one-seat margin, threatens to imperil the Trump agenda and puts emphasis on the need to pass tax reform before Jones is seated.

Trump, sitting in the White House earlier Wednesday with Republican lawmakers tasked with negotiating the final deal, said holding the tax vote quickly is important not just because of the lost Senate seat.

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