Outspent by nearly a 2-1 ratio by Hillary Clinton and conspicuously not endorsed by the two most recent Republican presidents or the two most recent Republican presidential nominees, Donald Trump was still able to capture six states Democrat Barack Obama had twice carried — Florida, Iowa, Michigan, Ohio, Pennsylvania and Wisconsin — and the White House.

But this was only, we recall, after Trump had single-handedly organized a hostile takeover of the Republican Party, which, less than a year previously, had generally stood for free markets, free trade, cutting spending on Social Security and Medicare, reforming the nation’s immigration system, and an activist, often hawkish, foreign policy. Trump won the Republican nomination on a platform of deporting all undocumented immigrants, preventing Muslims from entering the U.S., building a wall along the country’s southern border to keep Mexican “rapists” out, condemning the most recent Republican administration for taking the U.S. into war against Iraq while knowing full well that Saddam Hussein did not have weapons of mass destruction, billing himself as the only Republican who didn’t want to cut Social Security and blaming “stupid” negotiators for free trade agreements that benefited elites while destroying American jobs and industries.

And on Nov. 8, Trump successfully breached the Democrats’ vaunted “blue wall” of safe states and became the first Republican since Ronald Reagan in 1984 to carry Michigan, Pennsylvania and Wisconsin, and he helped the Republican Party hold on to its majorities in both the Senate and the House.

So why, then, with complete GOP control of the presidency and the Congress, is there an almost palpable nervousness among Republicans on Capitol Hill?

For starters, half the Republicans in the Senate and a solid majority of House Republicans have been elected (and re-elected) since 2010, when they had the advantage of being able to run on the political offensive as critics of President Obama’s policies. These Republicans have never served under a president of their own party, a task that requires you to defend or distance yourself politically from “your” president’s unpopular policies. In elections while George W. Bush was holding office, Republicans — playing defense — suffered a net loss of nine Senate seats and 45 House seats. Democrats in the Obama years fared even worse — holding today nine fewer Senate seats and 62 fewer House seats than they did eight years ago. Beginning in 2017, Republican candidates will be running on Trump’s record.

But the real concern for Republicans is the man himself. More than a month after his upset victory, Trump, according to the Gallup Poll, was still rated unfavorably by 55 percent of his fellow Americans, and barely 42 percent favorably graded the president-elect. Compare that with the ratings of his three immediate predecessors at the same stage — between election and before inauguration. Obama had a favorable rating of 74 percent, and Bush’s favorable rating was 62 percent. Bill Clinton’s was 65 percent.

In the wake of a bitter campaign, Trump has made no public effort to heal the deep divisions within the country. Instead, he has continued to campaign, holding rallies that energize his core supporters but feature Trump’s sustained, ungenerous taunts at his defeated opponent — with the crowd’s televised chants of “lock her up” encouraged — and only further aggravate the nation’s polarization. What all this means is that Donald Trump will take office with no presidential honeymoon.

For nervous Republicans, this means that President Trump, when the going gets rough, will have no cushion of public support to buoy him, and for GOP officeholders, Trump’s coattails could turn out to be a tank top.

Editor’s note: To find out more about Mark Shields and read his past columns, visit the Creators Syndicate website at www.creators.com.