Sen. Thom Tillis (R-N.C.) talks to reporters after the Senate vote on President Trump’s national emergency declaration. (Michael Reynolds/EPA-EFE/Shutterstock)

Sen. Thom Tillis took every possible position on President Trump’s declaration of a national emergency to build a wall along the Mexican border.

At first, Tillis (R-N.C.) stood defiantly against Trump’s usurpation of congressional prerogative, declaring in a Washington Post op-ed almost two weeks ago that approving the emergency would “justify providing the executive with more ways to bypass Congress.”

Then, over the past week, as political pressure mounted, Tillis moved into the undecided column in hope of a compromise with Trump. “I hate to be a broken record, but it’s a work in progress,” Tillis told reporters Wednesday.

By Thursday afternoon, as 12 GOP colleagues broke ranks with the president, Tillis instead fell in line.

“He’s willing to work with us,” the humbled senator, up for reelection in 2020, said in a speech just before voting against a resolution to block Trump’s emergency action.

Tillis remains hopeful that follow-up legislation might amend the law on emergency declarations despite negotiations breaking down with the president, including a rare late-night visit to Trump by a trio of GOP senators who left the White House empty-handed.

Tillis’s reversal summed up the state of the Senate GOP caucus well into year three of the Trump presidency. A growing number of Senate Republicans, Trump’s biggest check against congressional Democrats, have grown uneasy with the president’s executive actions both in diplomacy and in domestic politics.

On Wednesday, seven Republicans joined with all 47 members of the Democratic caucus to end U.S. military support for the Saudi-led war in Yemen, in part a reaction to Trump’s continued embrace of the Saudi Arabian crown prince, Mohammed bin Salman, after U.S. intelligence analyses determined he was behind the killing of Washington Post columnist Jamal Khashoggi.

On Thursday, a dozen Republicans joined all Democratic caucus members in approving a resolution that would overturn Trump’s emergency declaration, coming last month when he agreed to sign a spending bill for parts of the federal government over the border standoff.

Those back-to-back rebukes, in a normal White House, might send aides scrambling across the West Wing in fear of a growing backlash against Trump, particularly with the looming conclusion of special counsel Robert S. Mueller III’s investigation into the 2016 Trump campaign’s alleged ties to Russia.

But Tillis’s actions highlighted a hardening reality in Washington: Republicans who have real near-term political skin in the game are not willing to stand up to him.

Only 14 Republicans voted against Trump on either of the two resolutions opposing his executive powers, and Sen. Susan Collins (R-Maine) is the only one facing reelection in 2020 who voted against Trump on both resolutions.

Collins is a well-known moderate considered the lone Republican who can win in Maine, which has supported the Democratic presidential nominee in seven straight elections. She also built a reservoir of goodwill from Trump for her support of Justice Brett M. Kavanaugh during last fall’s Supreme Court nomination fight.

Of the 22 Senate Republicans on the ballot in November 2020, Trump went 20 for 22 on the Yemen resolution and 21 for 22 on the border wall.

Chief among those is Senate Majority Leader Mitch McConnell (R-Ky.), who pulled a slightly lower-profile version of Tillis’s reversal. McConnell initially opposed the emergency declaration and privately warned Trump in a White House meeting that he would face a significant bloc of GOP defections.

But Trump agreed to sign a new funding bill, rather than launch a new partial government shutdown, in exchange for McConnell’s support for Trump on the vote to block the emergency declaration.

Like most Republicans facing a reelection in 2020, McConnell’s most vulnerable election would come in a GOP primary, particularly if Trump does not vociferously support the 34-year veteran of the Senate.

McConnell declared that the existing law gives any president broad powers and that, rather than stand up to Trump now, Congress should consider changing the law sometime down the road. “The president is operating within existing law and the crisis on our border is all too real,” he said during a Thursday morning speech.

Nationally, 90 percent of Republicans approve of Trump’s job performance, according to a Gallup poll released Thursday. And the president made clear that votes against him were an act of betrayal.

“A vote for today’s resolution by Republican Senators,” Trump tweeted Thursday morning, “is a vote for Nancy Pelosi, Crime, and the Open Border Democrats!”

There’s no way to win reelection if you don’t first win the GOP primary, so even Republicans who could face difficult general elections lined up behind Trump rather than risk his wrath.

Sens. Cory Gardner (R-Colo.), Joni Ernst (R-Iowa) and Martha McSally (R-Ariz.) voted to support Trump this week. Ernst came out early in support, while McSally said she received assurances that no emergency funds would be pulled from Arizona’s military projects to support new wall construction.

Gardner simply kept his head down for weeks, avoiding a public position until Thursday.

Tillis narrowly won his first race in 2014, a great year for the GOP, and now must run in a presidential year with much higher turnout.

So his original declaration against Trump’s emergency seemed to position him for the general election. He criticized conservatives who compared President Barack Obama earlier this decade to an “emperor” when he used executive powers to unilaterally grant protections to undocumented immigrants but refused to call out Trump.

“There is no intellectual honesty in now turning around and arguing that there’s an imaginary asterisk attached to executive overreach,” he wrote in his op-ed.

Early last week Tillis continued to stand his ground. “It’s never a tough vote for me when I’m standing on principle,” he told reporters March 5.

By late last week, as Trump increased his public pressure, some North Carolina Republicans began looking for a conservative challenger to Tillis in the GOP primary next spring.

Early this week Tillis began publicly wavering and supported the effort to rewrite the emergency law. He acknowledged, in his speech before the vote, that he had “received a lot of feedback” after his initial position, including from the White House.

“I think we can view this as an opportunity,” Tillis said of his reversed position.

Correction: An earlier version of this story described Senate Majority Leader Mitch McConnell (R-Ky.) as having a 32-year Senate career. He took office in 1985 and has a 34-year career in the Senate. This story has been updated.

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