When the clock strikes midnight, the US government could shut down in historic fashion.
If a deal isn't reached, it will be the first modern shutdown with Congress and the White House controlled by the same party.
The last shutdown occurred in 2013 during the Obama administration
When Ronald Reagan was in office, there were three partial shutdowns
While some form of a government shutdown occurred during the Obama, Clinton, HW Bush, and Reagan administrations, these occurred while Democrats and Republicans split control of the White House and at least one chamber of Congress.
The last shutdown occurred during the Obama administration. It lasted 16 days, from October 1, 2013 to October 17, 2013. The Democrats had control of the White House and the Senate, while the Republicans controlled of the House.
During the Clinton administration, there were two shutdowns. The first lasted five days, from November 14 to November 19, 1995. The second lasted 21 full days, from December 16, 1995 to January 5, 1996. It was the longest shutdown in history. At the time, Democrats controlled the White House, while Republicans controlled the House and Senate.
The only shutdown during George H.W. Bush's administration occurred during the three days of Columbus Day weekend from October 6 to October 9, 1990. At the time, Republicans controlled the White House, while Democrats controlled both the House and Senate.
When Ronald Reagan was in office, there were three partial shutdowns in 1981, 1984, and 1986. These resulted in mostly half-day layoffs of federal workers. Republicans had the White House and Senate during these times, while Democrats controlled the House.
'Funding gaps' before Reagan
The government didn't face shutdowns as we know them before the 1980s. When there was a funding gap, employees continued work as usual under the assumption Congress would pass a measure.
During Jimmy Carter's administration, when Democrats controlled the White House and all of Congress, there were five spending gaps between 1977 -- 1979 that lasted at least eight days each.
Carter's Attorney General, Benjamin Civiletti, issued new guidelines in 1980 and 1981 under the Antideficiency Act, instructing federal agencies to limit work to only essential operations and obligations during funding gaps.
Under the law, he said, if the government didn't have money from Congress, it would not be allowed to function.
Without those stricter guidelines, the government could -- and frequently did -- function without funds to pay their expenditures.
Civiletti's interpretation of the law in 1980 changed that. He issued his first ruling in the midst of a standoff over funding for the Federal Trade Commission.
Congress failed to pass an authorization bill before their old one ended, leaving them without money after April 30, 1980. According to The Washington Post, federal agents came to some regional offices with an order for employees to cease operations.
Without funds, the FTC closed its doors to confusion and frustration among its over 1,000 employees on May 1, 1980. Congress took note and quickly passed an authorization bill that day, which Carter signed in the evening, and the Commission opened its doors the next day.
Thus began the modern-day shutdown.