WASHINGTON — The television is on. The phone is never far away. And President Trump is repeatedly calling allies such as members of Congress and conservative radio hosts, telling them privately that he will not give in on his demand for funding for a border wall.

What the president who campaigned on his ability to cut deals has not done, nine days into a partial government shutdown over his signature campaign issue, is reach out to Democratic congressional leaders to strike one.

Virtually alone in the West Wing since the shutdown began, Mr. Trump has instead taken to Twitter to excoriate Democrats, and highlight that he canceled his own vacation to his private club in Florida while lawmakers left the city. He has lamented the negativity of the news media coverage, which has included repeated airings of Mr. Trump’s declaration in the Oval Office a few weeks ago that he would not blame Democrats for a shutdown, according to people familiar with his thinking.

Even as some lawmakers floated compromises on Sunday, Democrats prepared to pass a bill to fund the government as soon as they take control of the House on Thursday. Like the Democrats, Mr. Trump appears to have dug in. And the uncertainty over what he might sign threatens to indefinitely drag out a shutdown that has affected 800,000 federal workers and shuttered parts of nine cabinet-level departments.