Vice President Joe Biden talks with Costco employees in the bakery section of the store while shopping at a Costco in Washington, Thursday, Nov. 29, 2012. Biden went shopping for presents and to highlight the importance of renewing middle-class tax cuts so families and businesses have more certainty at this critical time for our economy. (AP Photo/Susan Walsh)

Vice President Joe Biden visits with patrons over lunch at Cruisers Diner, Sunday, Sept. 9, 2012, in Seaman, Ohio. (AP Photo/Carolyn Kaster)

Vice President Joe Biden (seen here at a rally in Philadelphia on Sunday) rallied union workers to turn out the vote for Gov. Quinn on Tuesday.

Vice President Joe Biden laughs during a campaign rally at Lakewood High School, Sunday, Nov. 4, 2012, in Lakewood, Ohio. (AP Photo/Matt Rourke)

Vice President Joe Biden followed by his daughter Ashley Biden, arrives on Air Force Two at Lexington Blue Grass Airport, Thursday, Oct. 11, 2012, in Lexington, Ky. (AP Photo/Pablo Martinez Monsivais)

Vice President Joe Biden speaks during a campaign event at West York Area High School, Sunday, Sept. 2, 2012, in York, Pa. (AP Photo/Carolyn Kaster)

FILE - In this March 23, 2010 file photo, President Barack Obama and Vice President Joe Biden, right, smile in the East Room of the White House in Washington, before the president signed the health care bill. At the bill signing, Biden was heard using the F-word on live television in a whispered congratulations to Obama. While foul language has been uttered in politics before, a recent blue streak is making some wonder whether it reflects the coarsening effects of pop culture, a decline in public discourse, a desire by politicians to come across as average Joes, or just a really hot summer. (AP Photo/Charles Dharapak, File)

Vice President Joe Biden hugs Ivey Stewart, a Costco employee, after shopping at Costco in Washington, Thursday, Nov. 29, 2012. Biden went shopping for presents and to highlight the importance of renewing middle-class tax cuts so families and businesses have more certainty at this critical time for our economy. (AP Photo/Susan Walsh)

FILE - In this Friday, Feb. 11, 2011 photo by Associated Press photographer Ed Reinke, Vice President Joe Biden speaks at the McConnell Center at the University of Louisville in Louisville, Ky., Friday, Feb. 11, 2011. Reinke, an award-winning AP photographer who traveled worldwide and was known for his striking pictures of Kentucky news and sporting events, died Tuesday, Oct. 18, 2011 following an injury, according to his family. He was 60. (AP Photo/Ed Reinke)

Vice President Joe Biden addresses the Democratic National Convention in Charlotte, N.C., on Thursday, Sept. 6, 2012. (AP Photo/J. Scott Applewhite)

US Vice President Joe Biden talks on an employee's cellphone during a visit to a Costco store on a shopping trip in Washington, DC, on November 29, 2012. Biden made the visit to the first Costco store located in Washington, DC, during its grand opening. AFP PHOTO / Saul LOEBSAUL LOEB/AFP/Getty Images

Vice President Joe Biden shakes hands with Costco CEO Craig Jelinek, right, as co-founder Jim Sinegal watches at center, after Biden arrived to shop at the new Costco store in Washington, Thursday, Nov. 29, 2012. Biden went shopping for presents and to highlight the importance of renewing middle-class tax cuts so families and businesses have more certainty at this critical time for our economy. (AP Photo/Susan Walsh)

In this photo provided by Comedy Central, Vice President Joe Biden, left, joins host Stephen Colbert on the set of the "Colbert Report," Wednesday, Sept. 8, 2010, in New York. (AP Photo/Comedy Central, Scott Gries) NO SALES

** RETRANSMISSION OF BAG102 ** U.S. Vice President Joe Biden, center left, shake hands with Gen. Ray Odierno, right, on his arrival, in Baghdad, Iraq, Monday, Aug. 30, 2010. Vice President Joe Biden returned to Iraq Monday to mark this week's formal end to U.S. combat operations and push the country's leaders to end a six-month postelection stalemate blocking formation of a new government. (AP Photo/Hadi Mizban)

Standing amid members of the Euclid High School marching Band, Vice-President Joe Biden whistles to get someone's attention following a campaign stop at a fire station in Euclid, Ohio, Tuesday, Nov. 15, 2011. (AP Photo/Amy Sancetta)

Vice President Joe Biden talks with Costco employees in the bakery section of the store while shopping at Costco in Washington, Thursday, Nov. 29, 2012. Biden went shopping for presents and to highlight the importance of renewing middle-class tax cuts so families and businesses have more certainty at this critical time for our economy. (AP Photo/Susan Walsh)

Vice President Joe Biden speaks following a Senate Democratic caucus meeting about the fiscal cliff on Capitol Hill on Monday, Dec. 31, 2012 in Washington. (AP Photo/Alex Brandon)

Vice President Joe Biden's talks to customers during a stop at Cruisers Diner, Sunday, Sept. 9, 2012, in Seaman, Ohio. (AP Photo/Carolyn Kaster)

Rahm Emanuel before he takes his oath to become the new Mayor of Chicago with VP Joe Biden and wife Amy Rule and Dr. Jill Biden. | Al Podgorski~Chicago Sun-Times

Vice President Joe Biden leaves Dairy Queen with an ice cream cone and holding the hands of a little girl, Saturday, Sept. 8, 2012, in Nelsonville, Ohio. (AP Photo/Carolyn Kaster)

Vice President Joe Biden, his wife Jill Biden, left, and Foreign Secretary William Hague, right, arrive at the White House in Washington, Wednesday, March 14, 2012, before the State Dinner. (AP Photo/Susan Walsh)

U.S. Vice President Joe Biden, right, meets Mongolian wrestler during Mini Nadam, or Mongolian wrestling performance, in Ulan Bator, Mongolia, Monday, Aug. 22, 2011. (AP Photo/Andy Wong)

Sen. Tammy Baldwin, D-Wis. is kissed by Vice President Joe Biden during a mock swearing in ceremony on Capitol Hill in Washington, Thursday, Jan. 3, 2013, as the 113th Congress officially began. (AP Photo/Cliff Owen)

Republican vice presidential candidate, Rep. Paul Ryan, R-Wis., right, greets Vice President Joe Biden at the beginning of the vice presidential debate, Thursday, Oct. 11, 2012 at Centre College in Danville, Ky. (AP Photo/Mary Altaffer)

Sen. Tammy Baldwin, D-Wis. is hugged by Vice President Joe Biden during a mock swearing in ceremony on Capitol Hill in Washington, Thursday, Jan. 3, 2013, as the 113th Congress officially began. (AP Photo/Cliff Owen)

Vice President Joe Biden greets retiring Rep. Gabrielle Giffords, D-Ariz. on Capitol Hill in Washington, Tuesday, Jan. 24, 2012, prior to President Barack Obama's State of the Union address. (AP Photo/Pablo Martinez Monsivais)

Republican vice presidential nominee Rep. Paul Ryan, of Wisconsin, right, watches as Vice President Joe Biden, speaks during the vice presidential debate at Centre College, Thursday, Oct. 11, 2012, in Danville, Ky. (AP Photo/David Goldman)

President Barack Obama, left, and Vice President Joe Biden take their seats as they attend an Olympic men's basketball exhibition game between Brazil and Team USA in Washington, Monday, July 16, 2012. (AP Photo/Pablo Martinez Monsivais)

FILE - In this Oct. 2, 2012 file photo, Vice President Joe Biden speaks in Asheville, N.C. Four years ago, Biden was careful not to appear overly aggressive in his vice presidential debate with Sarah Palin, then a newcomer to the national stage. Now, as he prepares to debate Paul Ryan, a 14-year House veteran and the top Republican budget writer, Biden is less concerned about looking like a bully. (AP Photo/Chuck Burton, File)

FILE - In this Sept. 5, 2011 file photo, Vice President Joe Biden walks on stage past an Ohio state flag before speaking at an AFL-CIO Labor Day picnic, at Coney Island in Cincinnati. A year from Election Day, Democrats are crafting a campaign strategy for Biden that targets the big three political battlegrounds: Ohio, Pennsylvania, and Florida, states where Biden might be more of an asset to President Barack Obama's re-election campaign than the president himself. (AP Photo/Al Behrman, File)

FILE - In this March 23, 2010, file photo President Barack Obama and Vice President Joe Biden react to cheers as they arrive in the East Room of the White House in Washington for the health care bill. A year from Election Day, Democrats are crafting a campaign strategy for Biden that targets the big three political battlegrounds: Ohio, Pennsylvania, and Florida, states where Biden might be more of an asset to President Barack Obama's re-election campaign than the president himself. (AP Photo/J. Scott Applewhite, File)

Vice President Joe Biden and Republican vice presidential nominee Rep. Paul Ryan of Wisconsinface off in a debate on Oct. 11 at Centre College, in Danville, Ky. | Rick Wilking~AP

Vice President Joe Biden stands for a photograph with Firefighters Union Local 352 911 supervisor Starletta Diggs, of Flint, Mich., after speaking to public safety officers at a fire department building to promote the American Jobs Act, which he said would pump $5 billion into supporting jobs for police and firefighters, on Wednesday, Oct. 12, 2011, in Flint. (AP Photo/Detroit News, Charles V. Tines) DETROIT FREE PRESS OUT, NO MAGS, NO SALES, NO TABS, MANDATORY CREDIT

Vice President Joe Biden, center, jokes around with Owen Murphy, son of Sen. Chris Murphy, D-Conn., second from right, before a mock swearing-in ceremony for the 113th Congress, Thursday, Jan. 3, 2013, in the Old Senate Chamber on Capitol Hill in Washington. From left are Owen; Murphy's wife Catherine Murphy, Biden, Murphy, and son Rider. (AP Photo/ Evan Vucci)

Vice President Joe Biden and Republican vice presidential nominee Rep. Paul Ryan of Wisconsin shake hands after the vice presidential debate at Centre College, Thursday, Oct. 11, 2012, in Danville, Ky. (AP Photo/Pool-Michael Reynolds)

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