They voted to "drain the swamp" in Washington, D.C., but on the night before Donald Trump was sworn in as the 45th president of the United States, they came to wallow in it.

At parties across the city, Trump supporters danced and drank to celebrate an incoming president that they said would shake up a city that they saw as corrupt, complacent and out of touch with the rest of America.

"Washington is freaked out. They're about to lose power," said John Workman, a former mayor of Palm Beach Shores, Florida, as a pair of costumed robots danced to "Sweet Home Alabama."

Ironically, Workman and other Trump supporters were participating in a Washington ritual as old as the city itself - the crush of balls, parties and protests that mark the inauguration of a new U.S. president.

Trump takes office after a bitter presidential campaign marked by allegations of sexual harassment, race baiting and foreign hacking, and some of the parties were apparently as divisive as the president-elect himself.

Outside the DeploraBall, a gathering of tech-savvy Trump backers who take pride in offending liberals, several hundred protesters shouted obscenities as they squared off with riot police on the streets.

Police deployed chemical spray after protesters threw trash at those leaving the building, according to the Washington Post.