Other readings for Trump in the poll also showed signs of serious trouble. A 53 percent majority said Trump is "not honest" and 62 percent that he is "not level-headed." On average, Trump has a 48.7 percent unfavorable rating among Americans to 42.7 percent favorable.
Trump's inauguration next Friday might improve these numbers if he can deliver a unifying speech and convince Americans that he has clear plans to spark economic growth and ease fears that he is a thin-skinned hot head prone to lashing out at even the slightest criticism. But major protests planned for the inaugural weekend could dampen some of these efforts and galvanize Trump's opposition.
Trump also faces a broader problem once he takes office. His priorities are not widely shared by the American public. A new poll conducted for Politico and the Harvard T. H. Chan School of Public Health found that the top three priorities for Trump voters are repealing and replacing Obamacare (85 percent), stopping future illegal immigration (78 percent) and major increases in defense spending (67 percent).
The numbers are much lower for the general public. Just 44 percent say repealing at replacing Obamacare should be a top priority while 38 percent say immigration and 43 percent say increased defense spending.
The most popularity priority for the general public at 49 percent — major government spending on infrastructure — is the least popular among Trump voters at 50 percent. There are also major differences on immigration in general. Fully 57 percent of Trump voters view undocumented immigrants living in the U.S. as a "very serious problem" compared with just 30 percent of the general public. The public at large is also much more inclined to support a path to citizenship for undocumented immigrants than are Trump voters.
On taxes, the poll found that "a majority of both the general public and Trump voters oppose lowering taxes on big businesses and upper-income Americans. … Only 39 percent of Trump voters and 22 percent of the general public believe corporate taxes should be lowered. Only 18 percent of Trump voters and 13 percent of the public think taxes on upper-income Americans should be lower." Trump's initial agenda includes major tax cuts for both individuals and corporations.
Trump and the Republican Congress will also be on very dangerous ground making repeal of the Affordable Care Act — without an immediate replacement that ensures people are not deprived of existing coverage — their first agenda item.
For the moment, Trump's deep unpopularity does not appear to be a problem for him with the Republican Congress. The president-elect remains popular with an aggressive base that delivered him an Electoral College win even as he lost the popular vote by 3 million. Most Republicans on Capitol Hill live in fear of crossing Trump and angering his supporters.
That means the incoming president will get most or all of his Cabinet picks confirmed and will have a relatively free hand in passing his congressional agenda. But if Trump's approval rating sinks further, the president-elect could wind up ceding the agenda to Republicans on Capitol Hill, led by House Speaker Paul Ryan.
Ryan and the rest of the GOP won't hesitate to move to protect their own political futures ahead of the 2018 midterm elections if it appears the occupant of the White House is dragging them down.
And should Trump wind up in significant trouble over his own business conflicts or his relationship with Vladimir Putin and the Russians, he could wind up relying on a Republican Congress that views him as radioactive.
—Ben White is Politico's chief economic correspondent and a CNBC contributor. He also authors the daily tip sheet Politico Morning Money [politico.com/morningmoney]. Follow him on Twitter @morningmoneyben.