Democrats said Thursday that White House adviser Karl Rove (search) should either apologize or resign for accusing liberals of wanting "therapy and understanding" for the Sept. 11 attackers, escalating partisan rancor that threatens to consume Washington.

Rove's comments — and the response from the political opposition — mirrored earlier flaps over Democratic chairman Howard Dean's (search) criticism of Republicans, a House Republican's statement that Democrats demonize Christians and Democratic Sen. Dick Durbin's comparison of the Guantanamo prison to Nazi camps and Soviet gulags.

White House press secretary Scott McClellan (search) came to Rove's defense, saying the president's chief political adviser was "simply pointing out the different philosophies and different approaches when it comes to winning the war on terrorism."

"Of course not," McClellan said when asked by reporters whether President Bush will ask Rove to apologize.

Rove, in a speech Wednesday evening to the New York state Conservative Party just a few miles north of Ground Zero, said, "Liberals saw the savagery of the 9/11 attacks and wanted to prepare indictments and offer therapy and understanding for our attackers." Conservatives, he said, "saw the savagery of 9/11 and the attacks and prepared for war."

He added that the Democratic Party made the mistake of calling for "moderation and restraint" after the terrorist attacks.

During the 2004 campaign, Bush dismissed the notion of negotiating with terrorists and said, "You can't sit back and hope that somehow therapy will work and they will change their ways."

Rove's comments quickly escalated the bitter divide between the parties that could get worse as Congress prepares for what may be a drawn-out political fight, possibly this summer, over a Supreme Court nominee.

New York Sen. Charles Schumer said Rove "took something that is virtually sacred to New Yorkers" — the tragedy of the Sept. 11 attacks — "and politicized it for political, opportunistic purposes."

"Karl Rove is not just another political operative," added New York's other Democratic senator, Hillary Rodham Clinton. "He sits in the White House, a few doors down from the president."

At a Senate Armed Services Committee hearing Thursday, Clinton urged Defense Secretary Donald H. Rumsfeld to repudiate the "insulting comment."

Rumsfeld replied that it "is unfortunate when things become so polarized or so politicized."

Schumer and Clinton joined the four Democratic senators from Connecticut and New Jersey in a letter to Rove requesting that he immediately retract his comments. "To try to score partisan, political points at the expense of the 3,000 victims and their families was unacceptable and opportunistic," they wrote.

Rep. Jerrold Nadler, D-N.Y., wrote a similar letter to Rove from House Democrats.

Schumer said Rove's comments might have been made in the heat of the moment and he was willing to accept an apology. But "if they try to stonewall," he said, "then I think resignation would be called for."

Senate Minority Leader Harry Reid, D-Nev., also said Rove, the political mastermind behind Bush's election victories, should fully apologize for his remarks or resign. Dean said Bush should "condemn Karl Rove's desperate and divisive attempt to help the Republicans regain their political footing."

Republicans, meanwhile, have recently condemned House Minority Leader Nancy Pelosi, D-Calif., for calling the Iraq War a "grotesque mistake," and demanded and finally got an apology from Durbin for his linking detainee abuse and Nazis.

And they were unapologetic about Rove's comments.

"The Republican leadership priority is to have our troops hunt down, kill or capture terrorists before they try to attack us again at home," said Ron Bonjean, spokesman for House Speaker Dennis Hastert, R-Ill.

"The Democratic leadership priority is to actively engage in the politics of division and distraction that can undermine our national security in favor of a left-wing agenda," he said.

Increasing public doubts about the Iraq war have emboldened Democrats to challenge the president's policies. Republicans, in turn, contend that criticism undermines the war on terror.

New York Mayor Michael Bloomberg, a Republican running for re-election in an overwhelmingly Democratic city, issued a statement urging both sides to keep politics out of the war on terrorism. "We owe it to those we lost to keep partisan politics out of the discussion and keep alive the united spirit that came out of 9/11," he said.