Brazil has been campaigning for the Security Council seat on the strength of its economic growth, which its officials say gives the Latin American country the necessary financial clout and rightful leadership in the region.
So far Brazil's claim has gone largely uncontested, except for minor murmurings of dissent, and Brasilia hopes the U.S. president's visit will be the right moment to win crucial diplomatic support.
Brazilian officials see Obama's visit as an opportunity to consolidate ties with Washington on a more equitable basis and to offer Obama the idea that Brazil and the United States can become equal partners in business and trade, diplomacy, politics and regional relations.
Outgoing President Luiz Inacio Lula da Silva earned the ire of U.S. diplomats and policymakers with frequently strident comments critical of the U.S. administration, and by pursuing policies favorable to Iran that Americans saw running counter to U.S. interests.
President Dilma Rousseff, who took office in January, has demonstrated more subtlety and tact in dealing with the United States, offering business opportunities while giving little away in terms of her pursuit of exchanges and deals that ensure continued Brazilian pre-eminence in regional international relations.
A permanent Security Council seat will confirm Brazil's position as a regional power even as other countries, particularly Chile, have been more forthcoming in building ties with Washington.
Argentina has already expressed displeasure over what it sees as relegation to a second or third place in the unwritten pecking order in relations between North and South America.
Obama's visit, starting Saturday, will signal the start of a new phase in Brazilian-U.S. relations, Steven Bipes, executive director of the Brazil-U.S. Business Council, said in comments to the media.
"I do expect some significant announcements that will take the relationship to the next level," he said.
Brazilian business sources and officials expect progress on a trade and investment framework agreement that will create a forum for exploration avenues for bilateral expansion. Bipes said a new agreement could be signed and lead to negotiations on a free trade pact.
However, he said, a trade accord would need to be within the framework of a Mercosur regional trade pact, implying that any such new arrangement would also involve Argentina, Uruguay and Paraguay, the other full members of the group.
Brazilian business leaders are also pinning hopes on progress toward a bilateral tax treaty. Rousseff is likely to discuss biofuels, one of Brazil's major strengths and greater transfer of nuclear technology.
U.S. Trade Representative Ron Kirk, Commerce Secretary Gary Locke and Energy Secretary Steven Chu are to accompany Obama.
U.S. officials hinted to optimism over the visit existed on both sides. Mike Froman, deputy national security adviser for international economic affairs, said Brazil's 7.5 percent economic growth in 2010 and the $80 billion trade turnover with the United States opened new possibilities. U.S. exports to Brazil have doubled over the past five years.
Bipes advised the media not to look for major breakthroughs on trade, but added, "I expect some things to come out of this that are not on our radar."