Columnist

When Republicans brought their budget to the Senate floor last week, they were bracing for what is known on Capitol Hill as a "vote-a-rama," in which Democrats would keep the Senate in session until the wee hours, forcing Republicans to cast dozens of politically toxic votes on everything from gun control to legalizing the immigration status of Deferred Action for Childhood Arrivals recipients.

But the "vote-a-rama" never materialized. Democrats simply stood down.

Why? Because they knew that what was toxic for Republicans would be even more toxic for vulnerable Senate Democrats running for reelection in states President Trump won by double digits. Democrats are deeply worried about the fates of Sens. Joe Manchin III of West Virginia (which Trump won by 42 points), Heidi Heitkamp of North Dakota (which Trump won by 36), Jon Tester of Montana (20), Claire McCaskill of Missouri (19) and Joe Donnelly of Indiana (19). If Trump can pick off some or all of these seats, then he could finally have what he needs to pass key legislation with GOP votes alone. And the Democrats' chances of taking control of the Senate two years later in 2020 could slip away.

This is good news for Republicans, but especially for Trump's efforts to pass tax reform. If Democrats are running scared in red states, then Trump can turn the screws on them to vote with him or pay a price in November.

For a while, it appeared Trump was actively courting these Democrats. In September, he hosted Heitkamp, Manchin and Donnelly for dinner at the White House to discuss tax reform. That same month, he invited Heitkamp to travel with him on Air Force One to a tax rally in North Dakota, where he declared her a "good woman" and said his supporters are "for you, 100 percent." A few weeks later, he did it again, this time inviting Donnelly aboard Air Force One for a speech in Indiana unveiling the framework of his tax plan. There he took a sharper edge, warning "If Sen. Donnelly doesn't approve it . . . we will come here, we will campaign against him like you wouldn't believe," adding "I think we'll have numerous Democrats come across because it's the right thing to do." All good.

But after this initial burst of activity, it looks as if Trump may be giving up. "It'll be hard getting the Democrats because they are obstructionists and they vote in blocs," he told the Heritage Foundation last week, "but if we get the Republicans we need, which is virtually every single one of them . . . you will see things happen like have never happened before."

Giving up would be a mistake. With Obamacare, Republicans preemptively announced that they planned to pass the repeal-and-replace bill with only Republican votes. That let red-state Democrats off the hook, and they paid no price for voting against Trump. He should not let them get away with failing to cooperate this time. Instead, he should turn up the heat. His national approval rating is in the high 30s, but in West Virginia, North Dakota, Montana, Missouri and Indiana, it ranges from 49 to 60 percent, which means Trump will be a formidable opponent if these senators cross him. He should be a constant presence in their home states for the next two months, rallying voters behind his tax-reform plan and warning that its success or failure depends on how their Democratic senator votes.

If he turns up the pressure, he wins, no matter what. If the Democrats capitulate, tax reform will almost certainly pass — giving Trump the major legislative victory that has so far eluded him. If they vote against him in spite of such a campaign, then Trump has teed up the GOP for big gains in the Senate.

The only bad option is giving them a free pass again, so Democrats can claim that they would have happily supported the president if he had continued trying to work with them. If Trump fails to put the squeeze on them and does not pass tax reform, the odds of losing the Senate will grow. If Democrats win the Senate, the Trump presidency would effectively be over. No more judges, no more nominees. Democrats would control the Senate's investigative committees, handing them unbridled subpoena power. And, should they win the House as well, Democrats could have the votes to bring impeachment proceedings against Trump if they so choose.

In other words, the way forward for Trump is clear: Make Democrats vote for tax reform or pay a political price. Don't let them off the hook.

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