It’s fairly certain the government will shut down. If the Senate doesn’t pass the short-term spending bill —passed earlier by the House — by midnight Friday, it will happen.

Under a shutdown, thousands of federal employees would go without pay and national parks would close, among other things.

Here's a look at the key players and fallout from recent government shutdowns.

October 2013 

How it happened 

It's simple — the battle over health care closed the government.

That year, House Republicans, angered by President Barack Obama's Affordable Care Act, repeatedly offered resolutions during budget negotiations that would have defunded the health care law. These resolutions were rejected by the Democratic-controlled Senate, which led to a budget impasse.

The government shutdown for more than two weeks after Congress was unable to agree on a budget for the new fiscal year, leaving nearly 800,000 federal employees out of work without pay.

On the political front, there were ramifications.

Winners 

Sen. Harry Reid, D-Nev. 

The former Senate majority leader was a vocal Democratic critic of Republican-led efforts to defund President Obama's health care bill. He relentlessly castigated Republicans for their tactics to defund Obamacare, which ultimately led to the shutdown.

"You know with a bully you cannot let them slap you around, because they slap you around today, they slap you five or six times tomorrow. We are not going to be bullied," Reid told reporters.

In the end, Reid came out of the shutdown with a bolstered reputation as a fighter of Democratic causes and earned plaudits from Obama.

Obamacare 

At the time, the botched rollout of the health care law drew daily headlines. Websites for health care exchanges didn't work and the administration had few answers. Still, public scorn focused on Republicans as the government remained shuttered for 16 days. Republicans thought their efforts would prove fruitful.

Sen. John McCain, R-Ariz. 

In the months and weeks leading up to the shutdown, McCain served as a voice of reason for the Republicans. He insisted that it would be unwise for the party to allow a shutdown over Obamacare.

"I campaigned in 2012 all over this country for months: 'Repeal and replace Obamacare.' That was not the mandate of the voters. If they wanted to repeal Obamacare, the 2012 election would have been probably significantly different," he said at the time.

Ultimately his efforts faltered as Republicans charged ahead with efforts to defund Obamacare and the government shutdown.

Losers 

House Speaker John A. Boehner, R-Ohio 

He failed to rein in the most conservative grass-roots wing of his party. Boehner was the middle man of sorts in negotiations between Democrats, moderate Republicans and conservative activists. Two years later, he resigned because of the strong opposition he faced from the Republican caucus.

Sen. Ted Cruz, R-Texas 

While Cruz raised his national profile as a staunch critic of Obamacare, he also made a lot of enemies. Weeks before the shutdown he delivered a 21-hour talk-athon on the Senate floor, assailing the health care law — a move that drew scorn from Democrats and Republicans. Cruz's vocal opposition to the law helped establish him as a force within the GOP grass roots and set him up for a presidential run in 2016.

Rep. Debbie Wasserman Schultz, D-Fla. 

Public opinion polls consistently showed that Republicans were blamed for the government shutdown. Even so, the former Democratic National Committee chairwoman was unable to turn that into victories in the 2014 midterm. Many Democrats fault her leadership as a factor in the party's sweeping losses in that election.

In this April 26, 1995 file photo, President Bill Clinton meets with congressional leaders in the Cabinet Room of the White House in Washington. From left are, Treasury Secretary Robert Rubin, House Speaker Newt Gingrich of Ga., the president, and Senate Majority Leader Bob Dole of Kansas. Disputes over spending and health care in a divided Washington have triggered shutdowns of the federal government in recent years. Republicans now control the White House and Congress, and if lawmakers and President Donald Trump fail to agree on a spending bill by midnight Friday, a shutdown of an all-GOP government would occur for the first time in modern history.

Credit: Marcy Nighswander

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Credit: Marcy Nighswander

November/ December 1995 and January 1996 

How it happened 

This battle over funding Medicare, public education and environmental initiatives, pitted President Bill Clinton against Republican House Speaker Newt Gingrich. It turned into the longest government shutdown in the country's history. The shutdown came in two phases, with services shuttered from Nov. 14-19, 1995, then from Dec. 16 until Jan. 6, 1996. In total, the government closed for 27 days.

Winner 

President Clinton 

He stood firm in his battle with the Republican-controlled Congress. Clinton wanted a budget that increased expenditures on, among other things, Medicare and public education, but Republicans wanted to slow government spending. This led to months of negotiations _ the government closing, opening, then closing again _ and through it all, Clinton's public approval ratings only dipped slightly. He easily won re-election in November 1996.

Loser 

House Speaker Newt Gingrich, R-Ga. 

After sweeping gains in the 1994 midterm elections, Republicans were emboldened and ready for a showdown.

"He can run the parts of the government that are left, or he can run no government," Gingrich told reporters weeks before the first shutdown. "Which of the two of us do you think worries more about the government not showing up?"

News reports at the time also noted that Gingrich was open to a shutdown after Clinton made him exit the rear of Air Force One after the two attended the funeral of slain Israeli leader Yitzhak Rabin. The comments made the Republican leader appear petty. In the end, after weeks of a shutdown, Republicans ultimately conceded to Clinton and Democrats.

January 2018 

What's happening now 

The battle over the border wall and the fate of hundreds of thousands in the Deferred Action for Childhood Arrivals program have stalled budget negotiations. Throw in funding for the Children's Health Insurance Program, and the GOP is finding it difficult to get the necessary 60 votes to pass a temporary spending bill. The 30-day extension, which was passed by the House, would be the fifth temporary funding measure in the past year. If the Senate does not pass the extension by midnight Friday, there will be a government shutdown.

Key players 

President Donald Trump 

It's clear Trump does not like to lose and does not like bad headlines. By all accounts, Trump and his policies did not come out on top in the budget deal.

Trump blames the Democrats, tweeting they want “illegal immigration and weak borders.”

Senate Majority Leader Mitch McConnell, R-Ky.

McConnell said Americans would be watching to see "which senators make the patriotic decision" and which "vote to shove aside veterans, military families and vulnerable children to hold the entire country hostage... until we pass an immigration bill."

Senate Minority Leader Chuck Schumer, D-N.Y. 

"We can't keep kicking the can down the road," said Schumer, insisting on more urgency in talks on immigration. "In another month, we'll be right back here, at this moment, with the same web of problems at our feet, in no better position to solve them."

Schumer met with Trump at the White House on Friday afternoon to discuss a deal to keep the government open.

Voters 

Public opinion is not on Trump's side when it comes to talk about a government shutdown.

According to a Washington Post/ABC News poll, more Americans blame Trump and Republicans for a government shutdown. According to the Washington Post, a "48 percent plurality says Trump and congressional Republicans are mainly responsible for the situation resulting from disagreements over immigration laws and border security, while 28 percent fault Democrats."

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