In a rare partisan attack with personal overtones, the Bush administration accused Democrats yesterday of playing "a big role" in the collapse of the savings and loan industry and warned that if the Democrats try to make a political issue of the thrift scandal, "We're ready to play."

White House press secretary Marlin Fitzwater led the administration strike, saying there were "some disturbing signs" of Democratic attempts to exploit the issue politically and warning that "this plays both ways."

Fitzwater's comments set off an uproar in Congress, where members of both parties have been reporting that the thrift crisis is a growing concern among angry constituents who are beginning to learn the cost of the thrift collapse and complain that taxpayers should not be forced to bear the brunt of the costs of the cleanup.

The unexpected White House assault also came as House Democrats questioned regulators about the federal government's decision during the 1988 presidential campaign to delay closing a Colorado thrift whose board of directors included President Bush's son, Neil.

Kermit Mowbray, former president of the Federal Home Loan Bank in Topeka, Kan., said that two weeks before the election he was ordered by officials in Washington to put off shutting down the failing Silverado Banking, Savings & Loan Association until December 1988 although his staff had been prepared to act in October.

The House Banking, Finance and Urban Affairs Committee also got its most detailed accounting yet of Neil Bush's role in transactions at Silverado that, according to federal regulators, contributed to the thrift's demise. The Silverado cleanup is expected to cost taxpayers an estimated $1 billion.

In one case, Neil Bush reportedly failed to tell fellow board members of a promise by a business associate to pay $3 million to a company owned by Bush at a time the business associate was asking Silverado to forgive $8 million of $11 million in obligations to the thrift. {Details, Page G1.}

The government has estimated it would cost more than $180 billion today to bail out the thrifts that have failed and make good on their deposits. Others have estimated that when the cost is spread out over the next decade, it will reach $500 billion. Such escalating cost estimates have added to the political explosiveness of the thrift cleanup issue.

After Fitzwater's statement, Democrats erupted in a stream of speeches yesterday condemning the previous and current Republican administrations for their handling of the thrift crisis and attacking the spokesman for his attack. Sen. Timothy E. Wirth (D-Colo.) took issue with Fitzwater's suggestion that Democrats were to blame for a "decade of mismanagement and neglect," asking derisively, "Who ran the government during this decade of mismanagement and neglect?" Not the Democrats, he added.

Sen. David Pryor (D-Ark.) said Congress was negligent, primarily in failing to give Reagan administration witnesses lie-detector tests when they were testifying about potential troubles in the savings and loan industry. "This is where we were negligent," he said. "We should have put them under oath. We could not get the truth."

Democratic House leaders have been debating whether and how to put the issue to political use, officials said yesterday. A senior Republican source, meanwhile, said the White House and GOP "are not only not going to let them {the Democrats} have this issue, we might just make it our issue." The official cited not only well-known Democrats involved in thrift scandals but a string of lesser-known Democrats, suggesting a serious opposition research effort by Republicans.

"You've suddenly got Democrats around the country trying to wrap the S&Ls around the Republicans," said GOP pollster Bill McInturff. "I don't think it's stuck, but it's a good and helpful thing for the White House to make sure that everyone's fingerprints are on the murder weapon. They're smart to make sure everyone remembers there are a lot of Democrat fingerprints."

Fitzwater, in his regular midday briefing, invited reporters to "take a look" at the roles played by former House speaker Jim Wright (D-Tex.), former majority whip Tony Coelho (D-Calif.), former House Banking Committee chairman Fernand J. St Germain (D-R.I.) and two of the so-called Keating Five senators who are under investigation by the Senate ethics committee for alleged intervention with federal regulators on behalf of failed thrift executive Charles H. Keating Jr.

He cited Sens. Dennis DeConcini (D-Ariz.) and Donald W. Riegle Jr. (D-Mich.), but left off the list the one Republican among the five, Sen. John McCain (Ariz.), as well as Sens. John Glenn (D-Ohio) and Alan Cranston (D-Calif.).

Fitzwater took particular aim at freshman Sen. Bob Kerrey (D-Neb.), inviting the press "to take a look" at "Mr. Kerrey and some of his Nebraska accounts," and noting the senator had given a major speech last week tying the thrift scandal to the Bush administration. "I think Senator Kerrey and others are clearly trying to make it a campaign issue, and if they want to do it, so be it," Fitzwater said. "There are a lot of battles that can be fought on this turf, and we're ready."

Fitzwater declined to elaborate on his comment about Kerrey's "Nebraska accounts," but apparently this was a reference to a Nebraska thrift that failed when Kerrey was governor. In 1983, the Commonwealth Savings Co. of Lincoln failed and Kerrey acknowledged the state department of banking had failed to oversee the institution effectively and protect its depositors. Kerrey's opponent in his 1988 Senate race accused him of failing to monitor the oversight of the bank before its collapse.

"This is not just a political attack. . . . I see an abuse of power here," replied Kerrey in characterizing Fitzwater's statement as an "arrogant, sneaky maneuver" that raised broader questions about the administration's exercise of power to thwart inquiry by Congress into policy matters.

What the administration is saying is "don't be too critical, don't step over the line" or "we might have to leak to the press on you, we might have something in our files here on you, senator," said Kerrey.

Republicans as well as Democrats should speak up in defense of stronger regulatory efforts even if it means getting attacked by "mean-spirited, angry little spokespersons," Kerrey added.

Fitzwater and others in the administration said yesterday's surprise attack was not ordered by Bush or prearranged. They said it grew out of a meeting Bush had earlier in the day with 18 Republican senators in which several of the lawmakers, led by Senate Minority Leader Robert J. Dole (R-Kan.), cited growing evidence that the Democrats planned to make Republican handling of the thrift crisis a major campaign issue this year and perhaps into the presidential election year of 1992.

Kerrey's speech on the issue, a speech last week by New York Gov. Mario M. Cuomo (D) and a speech by Riegle were cited as evidence. Each of the Democratic critics made the essentially populist argument that American taxpayers will be forced to bear the substantial costs of bailing out the thrift industry while the perpetrators of the collapse who grew rich were not being pursued.

One Republican official said that others in the meeting argued that "the Democrats are orchestrating it, have been for weeks now, and they better watch out because they don't come to this with clean hands and two can play at this."

In citing alleged Democratic sins, Fitzwater made only one general charge, noting, "A big part of the problem here is that in the dead of the night a few years ago, the Democrats pushed through raising the limits {on federal deposit insurance} to $100,000 per person. So there's a lot of cost to recover here."

That was a reference to the 1980 congressional approval of a major deregulation of the banking industry that included a provision raising from $40,000 to $100,000 the ceiling on federally insured bank accounts. Reports of the legislation and debate at the time showed no significant Republican opposition, with the legislation passing the House 380 to 13 and the Senate by a voice vote. One Republican who played a key role in pushing through the change was Sen. Jake Garn (Utah), the senior Republican on the Banking Committee at the time.

Despite continuing hearings on Neil Bush's role in the thrift collapse, Bush and his spokesman continue to shrug it off and cut short questions. Bush was asked last week whether his son should pay restitution for his role, and he said he disagreed "with the premise" of the question and turned to the next reporter. Yesterday, Fitzwater said Neil Bush had no role in the thrift crisis.

Staff writers Tom Kenworthy and Paul Taylor contributed to this report.