WASHINGTON – President Bush, faced with a string of setbacks on Capitol Hill, shrugged off questions about his political clout and promised yesterday to keep pushing the Republican-led Congress for a Social Security overhaul.

Looking ahead, the president also acknowledged he was thinking about a Supreme Court vacancy, widely expected this year. That was a departure from the White House’s usual refusal to publicly discuss how Mr. Bush would approach filling a job that, while not now empty, has groups across the political spectrum already gearing up for battle.

He pledged to consult senators at “an appropriate time,” though he didn’t say how early in the process those talks would come or whether he would seek input from Democrats as well as Republicans. He suggested that a recent compromise ending a Senate showdown over judicial nominees wouldn’t necessarily lead him to lean to a more centrist pick for the high court.

“I told the American people I would find people of a certain temperament that would serve on the bench, and I intend to do that,” Mr. Bush said in his seventh news conference in the seven months since his election to a second term.

Answering questions for 51 minutes in the sun-splashed Rose Garden, Mr. Bush said his policies in Iraq, Iran, and North Korea were working. He denounced as “absurd” a report by the human rights group Amnesty International that compared the U.S. treatment of terrorism suspects at Guantanamo Bay, Cuba, to a Soviet-era gulag.

Saying that Russian oil tycoon Mikhail Khodorkovsky seemed to have been “adjudged guilty prior to having a fair trial,” Mr. Bush promised to watch how the government of President Putin handled the expected appeal in a case regarded as politically motivated.

The president held firm to his domestic policy agenda even though Congress – including some Republicans – has balked at much of it. Mr. Bush is facing fights over his plan to partially privatize Social Security, his nomination of John Bolton as U.N. ambassador, a free-trade pact with Central America, an immigration guest worker program and his opposition to legislation to expand embryonic stem-cell research.

Mr. Bush professed no worries that he’s depleted most of the political capital he said that he earned with his re-election victory. Eager to dispel any notion that he is a lame-duck president with little leverage, Mr. Bush used the word “push” three times and “lead” four and showed no intention of giving up in any area.

“I’ve been around here long enough now to tell you, and tell the people listening, things just don’t happen overnight. It takes a while,” the president said. “And one thing is for certain, it takes a president willing to push people to do hard things.”

He indirectly criticized GOP Senate leaders for the delay in Mr. Bolton’s confirmation vote, which Democrats united to force.

“I was disappointed that once again the leadership there in the Senate didn’t give him an up-or-down vote,” Mr. Bush said.

On Social Security, Mr. Bush derided those who oppose his call for action as taking an “easy path.” He predicted success for his drive to create private accounts within the government retirement program.

“It’s like water cutting through a rock. It’s just a matter of time,” he said. “In the meantime, the people are watching Washington, and nothing’s happening, except you got a president who’s willing to talk about the issue.”

The Senate minority leader, Harry Reid, retorted that Mr. Bush should “stop caving to the demands of the far right” if he is serious about bipartisan accomplishment on any issue.

“Democrats stand in the commonsense center, ready to take up this work,” Mr. Reid, a Democrat of Nevada, said.

Turning to global matters, Mr. Bush repeatedly defended his approach to sticky problems:

Mr. Bush denied any increase of strength in the Iraqi insurgency, whose deadly attacks have been on the rise since a new government was announced April 28. He said the Iraqi government would be “plenty capable of dealing with them” with the help of American training. “I’m pleased with the progress,” Mr. Bush said.

He insisted that European-led talks with Iran “are making some progress” and defended his decision to allow Iran to apply for membership in the World Trade Organization as a key, but measured, step to advance those discussions.

Mr. Bush also defended his approach to North Korea, denying criticism that it has allowed the government there to expand its nuclear program. The president said trying to persuade Pyongyang to abandon the program through six-nation talks was still the most likely route to success.