WASHINGTON (CBSDC/AP) – For the first time in nearly two decades, the federal government staggered into a partial shutdown early Tuesday morning after congressional Republicans stubbornly demanded changes in the nation’s health care law as the price for essential federal funding and President Barack Obama and Democrats adamantly refused.

The stock market dropped Monday on fears that political deadlock between the White House and a Tea Party-heavy Republican Party would prevail, though analysts suggested significant damage to the national economy was unlikely unless a shutdown lasted more than a few days.

According to a study conducted by the Pew Research Center, the last government shutdown – which occurred in the 1996 fiscal year under the administration of then-President Bill Clinton – cost the nation an estimated $1.4 billion dollars.

In a release posted hours after the shutdown was announced, researchers at Pew found that the Office of Management and Budget estimated the cost of the shutdown, which took place from late 1995 to early 1996 and lasted a total of 26 days, was over the $1.4 billion mark.

“In a February 1996 letter, OMB provided other information about the FY1996 shutdowns,” officials said in a report obtained by Pew. “The information, which later was included in a congressional hearing print, included a list of effects from the shutdowns, lists of agencies and corresponding numbers of employees who were said to be excepted or not excepted from furlough, and a cost estimate of $1.4 billion for the shutdowns.”

Adjusting for inflation, Pew estimates that the total from the last shutdown would be closer to $2.1 billion today.

As Congress gridlocked, Obama said a “shutdown will have a very real economic impact on real people, right away,” with hundreds of thousands of federal workers furloughed and veterans’ centers, national parks, most of the space agency and other government operations shuttered.

He laid the blame at the feet of House Republicans, whom he accused of seeking to tie government funding to ideological demands, “all to save face after making some impossible promises to the extreme right wing of their party.”

House Speaker John Boehner, R-Ohio, responded a short while later on the House floor. “The American people don’t want a shutdown and neither do I,” he said. Yet, he added, the new health care law “is having a devastating impact. … Something has to be done.”

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