The South Korean has gained a reputation at the world body as a staunch friend of the US and its western allies, and has managed to keep China happy and placate Russia, UN officials and diplomats say.
His management of the big powers, they say, is why the secretary-general is set to breeze to victory tomorrow, when the 192-nation General Assembly votes on his reappointment.
Mr Ban is running unopposed and is seen winning handily, after Russia and the other 14 members of the UN Security Council endorsed his bid on Friday. His new term would start on 1 January, 2012.
Mr Ban's re-election would come in spite of a certain amount of dissatisfaction with him in the developing world. Some diplomats there complain that the former South Korean foreign minister has a tendency to echo the White House.
Arab envoys say Mr Ban's statements on the Israeli-Palestinian conflict are often similar to America's.
"You might want to call him a US 'yes man'," an African diplomat said.
But Mr Ban has won over a more powerful constituency - the five veto-wielding permanent members of the Security Council. In recent weeks, a White House spokesman credited him with "important reforms." French foreign minister Alain Juppe praised his "very solid experience."
UN officials deny that the secretary-general co-ordinates with Washington. "It isn't that we're Tweedledum and Tweedledee," a senior UN official said about Mr Ban and the US. "It's more that we see the world similarly."
Although Mr Ban has successfully navigated the often-competing interests of the five permanent Security Council members with the power to veto his second term, he has had run-ins with some of them.
Russia, several UN officials and diplomats claimed, went so far as to threaten to veto Mr Ban's second term because Moscow was unhappy with what it saw as his support for an independent Kosovo after the Albanian-majority government declared independence from Serbia in February 2008.