Rice spoke with Republicans for more than an hour and was to meet later in the day with Democrats.
Her visit came on the last of a three-day series of sometimes contentious congressional hearings, where there was bipartisan worry over whether the administration has a strategy for success in increasingly violent Iraq.
Those who met with her in the morning Republican session said it was upbeat.
"From my perspective, she gave a very upbeat report on how things are going there and the progress that's being made," said Sen. Rick Santorum of Pennsylvania.
"She answered question after question after question," said Rep. Deborah Pryce of Ohio. "We're on the right page and we're standing fully behind her."
Others said the subjects included the so-far lagging program to train Iraqis to take over their own security, the occupation authority's plan to hand over power to an as-yet unnamed Iraqi government June 30 and the fact that American troops will have to stay long after that to maintain security.
"Dr. Rice wanted to update Democrats and Republicans on key issues of governance, infrastructure and progress against the terrorists enemies on the ground," said Jim Wilkinson, deputy national security adviser.
Five hearings on Iraq this week produced some new details on Bush administration plans for the beleaguered campaign, but not all that lawmakers had hoped for. The final session was Thursday morning before the Senate Foreign Relations Committee.
Lawmakers are determined to keep pressing for details, partly because "inadequate planning" before the war caused some of the problems the U.S.-led occupation faces today, Sen. Dick Lugar, R-Ind. and committee chairman, said Thursday as he opened the hearing.
The Pentagon's top general said Wednesday that increased violence in Iraq is pushing the cost of the war over budget, threatening a $4 billion shortfall by late summer.
Gen. Richard Myers, chairman of the Joint Chiefs of Staff, said the recent decision to extend the stay of some 20,000 troops will cost roughly $700 million more over three months. And the White House kept open the possibility that it will seek additional funds before the end of this election year.
"When the service chiefs last talked about this, there was, I think, a $4 billion shortfall," Myers told the House Armed Services Committee. "We thought we could get through all of August. We'd have to figure out how to do September."
The war is costing about $4.7 billion a month, officials said. Defense officials are studying their budget, which runs through Sept. 30, to determine whether some money can be moved from purchase programs or other Pentagon accounts, Myers said.
Lawmakers expect to have a defense bill in place by the time the new budget year begins Oct. 1. But the version Mr. Bush proposed had no money for U.S. operations in Iraq and Afghanistan. Nevertheless, legislators say the Pentagon could use money from that bill until extra money for the war is provided.
White House officials have already said they would propose a separate bill after this fall's elections — costing up to $50 billion — to pay for the wars.
Rep. Duncan Hunter, R-Calif., chairman of the House Armed Services Committee, said he plans to attach an additional $20 billion for the 2004 year ending September to the 2005 defense bill now being considered.
Presidential spokesman Scott McClellan said Wednesday the final decision on what was needed — and when — would be "based on what the commanders in the field feel is necessary." McClellan said Pentagon officials have assured the White House they have the money they need.
On a day when nearly 70 people were killed by suicide bombers in Iraq's southern city of Basra, Myers and Deputy Defense Secretary Paul Wolfowitz testified for the second time in as many days.
Over the two days of hearings before three panels, lawmakers asked whether there are enough American troops in Iraq; how power can be handed over from the occupation authority June 30 to an Iraqi government that is yet to be chosen; what can be done to relieve the burden of repeated and extended deployments that have fallen on troops.
They also wanted to know what the Pentagon would do if more troops are needed; Myers said they're working up a plan for who could go. They asked whether more foreign troops might come; Wolfowitz said not many would as long as the violence continues.