WASHINGTON -- President-elect Barack Obama's choice for secretary of state, Hillary Rodham Clinton, asserted in confirmation hearings on Tuesday that the United States must lead the world with "smart power," and spent hours answering questions about her husband's financial dealings.

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"We must build a world with more partners and fewer adversaries," Clinton said before the Senate Foreign Relations Committee and a packed gallery. "American leadership has been wanting, but is still wanted."

Clinton said the United States cannot solve its most pressing problems "on our own" and said "the world cannot solve them without America."

Clinton, with daughter Chelsea in attendance, appeared likely to sail through Tuesday's hearing before the Senate Foreign Relations Committee, though some lawmakers were concerned that the global fundraising of her husband could pose ethical conflicts.

Sen. John Kerry, D-Mass., chairman of the committee, opened the hearing by welcoming Clinton's nomination, calling her "extraordinarily capable and smart."

Sen. Richard Lugar, the panel's ranking Republican, praised Clinton in his opening remarks, calling her "the epitome of a big leaguer" who is fully qualified for the job and whose presence at the State Department could open new opportunities for American diplomacy, including the possibility of improving the United States' image in the world.

However, Lugar also raised questions about the issue of former President Bill Clinton's fundraising work and its relation to his wife's new post.

Some Republicans on the panel asked whether Bill Clinton's charitable and business dealings might pose a conflict of interest.

His charitable foundation has accepted millions of dollars from foreign governments.

Kerry said that he and other senators want to know whether any overseas contributions might be excluded from the oversight requirement. He also said they want to know just how the process will work.

The line between Sen. Clinton's activities and her husband's foundation may not be a clear one.

An Associated Press review of her correspondence found that the secretary of state nominee intervened at least six times in government issues directly affecting companies and other organizations that later contributed to the foundation.

The letters and donations involve pharmaceutical companies and telecommunications and energy interests. A Clinton aide said the senator made no secret of her involvement in many of the issues and has acted "solely based on what she believes is best for the state and the people she represents" and no other factors.

Under an agreement with Obama, Bill Clinton recently released the names of donors to his foundation, but the foundation does not say when it received the donations or how much they were.

The nonprofit Clinton Foundation has raised nearly $500 million to fund the Clinton library in Little Rock, Ark., and charitable efforts around the world on issues such as AIDS, poverty and climate change.

In all Tuesday, five confirmation hearings were scheduled Tuesday for prospective Cabinet members in Obama's administration.

In additional to Sen. Clinton, appearing were Peter Orszag, his choice to head the Office of Management and Budget, and Robert Nabors II, for deputy director of OMB; New York housing official Shaun Donovan, to be secretary of housing and urban development; Steven Chu, to head the Energy Department; and Arne Duncan, as education secretary.

Meanehile, Treasury secretary designee Timothy Geithner is meeting with senators to discuss why he failed to pay personal taxes and check the immigration status of a housekeeper.

An official with Obama's transition office said Geithner answered senators' questions during a meeting he requested Tuesday. The person requested anonymity because the source is not authorized to speak publicly on Geithner's situation.

Obama's transition team was expected to release a statement about the issue later Tuesday.

Obama named the 47-year-old Geithner as his pick for Treasury secretary in November, citing as a top priority tackling the nation's financial crisis.