First Read is your briefing from Meet the Press and the NBC Political Unit on the day's most important political stories and why they matter.

WASHINGTON — The political situation we saw play out in 2009-2010 appears to be repeating itself. The party in power loses a Senate seat in stunning fashion; the environment it sees for the upcoming midterm season looks incredibly grim; despite it all, the party pushes ahead on a controversial legislative goal; and it believes the bill will finally become more popular when it passes into law.

"Our tax cuts will break down, and they'll break it down fast — all forms of government, and all forms of government barriers — and breathe new life into the American economy," Trump said yesterday. "Millions of middle-class families will win under our plan."

But here’s the thing: The tax plan that Republicans are trying to pass is as unpopular — if not more so — than Obamacare was at this same stage.

Do you approve or disapprove of the Republican tax plan? 26 percent approve, 55 percent disapprove (Quinnipiac poll — December 2017)

Do you approve or disapprove of the way Republicans in Congress are handling tax reform? 25 percent approve, 63 percent disapprove (Marist poll — December 2017)

Do you approve or disapprove of the Republican tax plan? 35 percent approve, 53 percent disapprove (CBS poll — December 2017)

Do you think Trump’s tax plan is a good idea or bad idea? 25 percent good idea, 35 percent bad idea (NBC/WSJ poll — October 2017).

By comparison, the March 2010 NBC/WSJ poll found Obamacare at 36 percent good idea, 48 percent bad idea.

And as Republicans race to pass the tax bill, they will find out — just as Democrats did in 2010 — there are plenty of glitches they’ll have to fix.

What’s inside the finalized GOP tax plan

Here are the details of the House-Senate deal on taxes that Republicans reached on Wednesday, per NBC’s Peter Alexander, Hallie Jackson and Ali Vitali:

“[T]he corporate tax rate would be cut to 21 percent, while the top tax rate for individuals would drop to 37 percent from 39.6 percent. The new rates would take effect next year.”

“The deduction for state and local taxes would be capped at $10,000 and taxpayers would be able to choose to deduct their property or income taxes, source said.”

“The standard deduction would be doubled under the deal, to $12,000 for individuals and $24,000 for families.”

“Republicans senators leaving a GOP lunch told NBC News that the agreement would also set deductions for pass-through income at 20 percent.”

“Under the deal, the mortgage interest deduction would be allowed on loans up to $750,000, the sources said.”

On “Today” this morning, Alexander reported that the deal also eliminates Obamacare’s individual mandate.

Moore refuses to concede

“A day after losing the Senate race in Alabama to Democrat Doug Jones, Roy Moore has issued a new statement refusing to concede the election until completion of the final count. But it wasn’t your typical post-election statement,” the Washington Post writes. “It was a four-minute fire-and-brimstone video about abortion, same-sex marriage, school prayer, sodomy and ‘the right of a man to claim to be a woman and vice versa.’”

On “Today” this morning, Jones said it was time for Moore to “move on.” “I understand the frustration,” he told NBC’s Savannah Guthrie. But: “It's time to move on.”

GOP steps up attacks on Mueller

The dispatch from NBC’s Ken Dilanian: “Republicans in Congress redoubled their attacks on the integrity of special counsel Robert Mueller's Russia investigation Wednesday, in what analysts believe is a concerted political strategy designed to discredit any potential Mueller findings that could argue for the impeachment of the president.”

“Seizing on newly released, politically charged text messages between two FBI officials who are no longer part of Mueller's investigation, Republicans used an oversight hearing of the House Judiciary Committee to accuse Mueller, a Republican, of conducting a tainted inquiry. They also charged that senior FBI officials have allowed political beliefs to influence the outcome of investigations.”

Washington’s Misconduct Watch

Here are the latest developments on two members of Congress — Reps. Blake Farenthold, R-Texas, and Ruben Kihuen, D-Nev.

CNN: “Michael Rekola, who was Farenthold's communications director in 2015, described in an interview with CNN new details of the congressman's abusive behavior. It ranged from making sexually graphic jokes to berating aides — bullying that Rekola says led him to seek medical treatment and psychological counseling, and at one point, caused him to vomit daily. One comment from the congressman was especially personal. Rekola was about to leave town to get married in July 2015, when, he said, Farenthold, standing within earshot of other staffers in his Capitol Hill office, said to the groom-to-be: ‘Better have your fiancée blow you before she walks down the aisle — it will be the last time.’”

The Nevada Independent: Once-rising Democratic star Rep. Ruben Kihuen made repeated and unwanted sexual advances toward a female lobbyist while he was a state senator, the woman told The Nevada Independent. The woman, who requested anonymity because of concerns about being identified and the possible consequences in Nevada’s small political world, says that Kihuen touched her thighs or buttocks on three separate occasions without her consent. She also showed the Independent hundreds of suggestive text messages she received from Kihuen — including invitations to come sit on his lap in the middle of a committee hearing and repeated requests to spend the night at her place — over the course of the 2015 legislative session.”