For a Blunt Biden, an Uneasy Supporting Role WASHINGTON - As President Obama reviewed the comedy routine he was to deliver at the recent White House Correspondents" Association dinner, one joke struck him as too hot. It suggested he might dump Vice President Joseph R. Biden Jr. from the ticket. Vice President Joseph R. Biden Jr. and President Obama at a rally in Cleveland in October 2010. "Four years ago, I chose Joe Biden as my running mate," Mr. Obama was to say, according to people familiar with early drafts of the planned remarks. Four years later, I'm almost positive I'm going with Joe again. He would then affect an exaggerated wink for the audience. But the president instructed his speechwriters to cut the line, figuring it would only inflame speculation from Beltway busybodies about his vice president's standing. Mr. Biden is also a bit raw on this topic. It goes to an essential insecurity that haunts almost every No. 2 - a job that the backslapping, shoulder-squeezing, muscle-car-loving Mr. Biden was wary of in the first place. Mr. Biden, 69, delights in speaking bluntly - even as that can complicate things for the White House, as it did Sunday when Mr. Biden said he was "absolutely comfortable" with same-sex marriage (an endorsement that went beyond Mr. Obama's statements on the issue). He loves to remind people that he did not have a boss for 36 years in the Senate, where he prided himself on being "my own man." He would tell aides and Senate colleagues that "my manhood is not for sale" if he felt pushed around. He told friends he feared that the vice presidency could be "emasculating." As he embarks on what could be his last campaign, Mr. Biden is also concluding a sometimes uneasy term, one marked by triumphs and occasional tensions with a boss markedly different in style and temperament. Almost by definition, his job is amorphous. "Being a vice president is kind of like being a first lady," Secretary of State Hillary Rodham Clinton said. You are there to support and serve the president. There is no job description. What job description there is often involves making the president look good. In recent weeks, Mr. Biden has given a series of heavily promoted policy speeches and assumed an attack-dog position in going after Mitt Romney, the presumptive Republican presidential nominee. Aides to Mr. Biden love to point out all the quality time he and the president spend together - including a golf outing last month - to accentuate their working bond. In his retelling of events, Mr. Biden always seems to be walking out of meetings with the president. Still, Mr. Biden's effort to subordinate his own voice (or manhood) to the broader enterprise has been a struggle. "In the good old days when I was a senator, I was my own man," Mr. Biden told reporters last December on Air Force Two. But now whatever I say is attributed to the administration. I finally learned that. He received a refresher course on Sunday after his comments about same-sex marriage on NBC's "Meet the Press." Administration officials spent the next few hours attempting to "clarify" Mr. Biden's remarks, setting off a new round of grumbling in the White House about Mr. Biden's message indiscipline. "Not helpful" is how one top Obama aide put the episode. As with any union of opposites, the one between the rambling vice president and his cautious boss has required time, patience and adjustments. Early on, for instance, it would drive Mr. Obama nuts to stand onstage waiting for Mr. Biden to introduce every dignitary in the room. So the president dispatched a top adviser, Valerie Jarrett, to relay his displeasure to Mr. Biden's office, according to top aides to both men. They initiated a fix: in future joint appearances, the president would remain offstage until the verbose vice president finished talking. For his part, Mr. Biden was annoyed by what he regarded as a slight by Mr. Obama. When Mr. Biden curiously told House Democrats that even if the administration did everything right, "there's still a 30 percent chance we're going to get it wrong," Mr. Obama responded to a reporter's question by saying he did not know what Mr. Biden was referring to. He tacked on a "not surprisingly" for good measure. At their next weekly lunch meeting, Mr. Biden complained that the quip was disrespectful, according to White House aides. Mr. Obama apologized but expressed his own frustration about Mr. Biden's verbal misadventures - called "Joe bombs" by some staff members during the 2008 campaign. Advisers describe the session as a tense but necessary clearing of the air that allowed them to move forward. A Utility Player