The Senate is expected to vote to raise the federal debt ceiling Tuesday at noon following passage in the House on Monday night, ending weeks of intense debate and threats of economic catastrophe. In the end, 59 of the 87 House Republican freshmen voted to raise the limit, just days after many of them rebelled against House Speaker John Boehner and refused to vote for his plan to raise the limit last week. How did it pass? First, there was a very important hallway.

The White House's "last play" was to have Vice President Joe Biden call his old pal, Senate Minority Leader Mitch McConnell, Politico reports. McConnell (pictured above, being hounded by reporters Sunday) wanted to protect the battered Boehner and avoid the appearance that they weren't working closely together. And post-deal, Republicans staffers' are keeping up the message. The New York Times, Politico, and The Hill all report that McConnell did a lot of walking back and forth between his office and Boehner's over the weekend:

Politico: 
Biden would make a proposal, and McConnell would pad the narrow, red-carpeted hallway behind the rotunda that links his office to Boehner's, staffers said. The speaker made the return trip several times himself, standing in shirtsleeves and puffing smoke as McConnell, a non-smoker, listened intently in the impeccable suit some aides suspect he wears 24 hours a day.
 
The Hill:
Careful not to get “cross-wise” with the House GOP leadership, according to one aide, McConnell shuttled back and forth from his office to Boehner’s office on Saturday and Sunday, acting as a broker between president and Speaker. He used the red-painted hallway connecting their offices, which is off-limits to reporters, to travel back and forth.
 
The Times:
The next morning Mr. McConnell was on two Sunday television shows, expressing optimism. Back at the Capitol, he ordered lunch, zipped back and forth through a back Capitol hallway to Mr. Boehner's office and talked five more times with Mr. Biden, aides say. 
 
Apparently the hallway was critical to the deal. Also critical: 
 
Biden: Politico reports that McConnell wanted his main partner in talks to be the vice president, because he thought "other Democrats, especially Obama, would prove to be less trustworthy bargaining partners."
 
Defense cuts: The plan forces spending cuts--50 percent of them to national security spending--if a special congressional commission can't come up with a broader plan to cut spending and reform entitlements and the tax code. A senior Democratic aide told Politico: "The defense cuts sold them. Basically $800 to $900 billion of the $2.1 trillion is in defense or security cuts... Biden kept saying, that when all things were factored in, it was basically a 50-50 on defense and domestic spending cuts."
 
2012: McConnell was very motivated to craft a deal, because he thought a default would be blamed on Republicans and ruin their chances of winning a majority in the Senate in the next elections, The Hill's Alexander Bolton reports.
 
A Moment of Clarity: Friday night, the House passed a debt limit bill that was quickly killed in the Senate. The Times' Jackie Calmes and Jennifer Steinhauer report that was the "nadir" of months of maneuvering. "Now I'm scared," an administration official told the Times then. Likewise, Politico reports that House Republican staffers were sick of meetings in the White House they called "joke meetings" or "Professor Obama's lectures."