The government entered a partial shutdown on Dec. 22, shuttering about 25 percent of the government and leaving hundreds of thousands of workers furloughed or forced to work without pay for the time being.

The shutdown began amid an impasse between the White House and lawmakers over Trump’s demand for billions of dollars in funding for a wall along the U.S.-Mexico border. 

…[Trump has] threatened to keep parts of the government shut down for years until he gets his desired funding to build the border wall. 

…The president first claimed in December that most of the federal employees impacted by the shutdown are Democrats, prompting backlash from lawmakers.

Trump: ‘I don’t care’ that most federal employees working without pay ‘are Democrats’ | TheHill