In 1974, as Watergate impeachment proceedings intensified against President Nixon, bitter criticism from influential Republicans helped persuade the president to step down.
One of the most staunch and powerful Republicans in Congress, for example, Sen. Barry Goldwater (R) of Arizona, berated Nixon for "sounding like a secondhand car salesman." Not long afterward, Nixon resigned.
Today, amid growing prospects that the House will vote next month for impeachment hearings, an embattled President Clinton is seeking to avoid a similar lashing by key congressional Democrats. Indeed, White House aides are making frequent pilgrimages to Capitol Hill to try to shore up the president's shaky standing within his party - even as signs of eroding support grow more ominous.
"There clearly is some hemorrhaging going on in the party," said Rep. James Moran (D) of Virginia. "The president has to come up with a way to stop this."
Democrats most likely to serve as bellwethers of the president's standing - and to influence his decisions - come from several camps, analysts say. They include not only party leaders such as Senate minority leader Tom Daschle of South Dakota, but also centrists such as Sens. Joseph Lieberman of Connecticut and John Breaux of Louisiana; liberals such as Sen. Edward Kennedy of Massachusetts; and Clinton loyalists such as Sen. Dale Bumpers of Arkansas.
Senator Daschel, known for having his hand on the pulse of the Democratic caucus, represents for Mr. Clinton a vital gauge of party sentiment. Similarly, Senator Lieberman is respected as an independent thinker from a wing of the party that is ideologically attuned with Clinton. Senator Kennedy, meanwhile, represents a seasoned voice of party liberals. And Senators Breaux and Bumpers (who is from Clinton's home state) are among the few members considered personally close to the president.
"Dale Bumpers and John Breaux are people who could pick up the phone and say: 'This is what you have to do,' " says Leon Panetta, Clinton's former chief of staff, now at California State University in Monterey. "They have a relationship that goes a little deeper."
Yet experts say that Clinton, in contrast to Nixon, is hampered in his ability to stem a slide in party support by two factors: his relatively weak alliances with Democratic lawmakers and the overall decline in party cohesion and discipline over the past two decades.
"Clinton is intensely his own operator. He has never had terribly strong relations with people on the Hill," says Sarah Binder, an expert on Congress at the Brookings Institution here.
"He does not have longstanding networks and friendships in Congress," agrees Stephen Hess, a senior fellow at Brookings, adding that "not one legislator owes his election to Clinton."
As a result, analysts say, Clinton personally cannot draw on a deep reservoir of goodwill on the Hill and is likely to be less effective as he appeals for forgiveness for having an affair with former White House intern Monica Lewinsky and lying about it.
Clinton is also at a disadvantage because Hill lawmakers - both Democrat and Republican - aren't as committed to party unity as in the past, experts say.
"Members in recent times have become islands to themselves in many ways," says Mr. Panetta. "The discipline that was a mark of the past is really not there."
The rise of "candidate-centered" politics predisposes today's lawmakers to place calculations of career self-interest above those of party loyalty, experts say.
All of this casts serious doubt over whether Democrats will continue in public to voice mostly muted criticism of the president's alleged misdeeds - even as they anguish in private about the potentially damaging impact the scandal could have on Democratic candidates in the November midterm elections. Pollsters predict Republicans will gain about 15 House seats, giving the GOP leadership a more comfortable margin in the majority.
Already, signs of party discord are growing.
This week, for example, congressional Democrats voiced impatience with Clinton's "hair-splitting" legal argument that his sexual encounters with Ms. Lewinsky did not constitute "sexual relations." Daschel, echoed by House minority leader Richard Gephardt (D) of Missouri, urged the president to stop the "legal jousting" that "serves no constructive purpose."
More bluntly, Rep. Harold Ford (D) of Tennessee called on the president to "come clean."
Daschel's remarks are a further indication that Democrats on the Hill are unwilling to blindly back the president or his strategy for self-defense.
In an earlier warning to Clinton that he cannot count on unconditional support from Senate Democrats, Lieberman on Sept. 3 boldly rebuked Clinton for his damaging "immoral" behavior - the first substantial public criticism of the president's actions from a Democrat.
Political observers stress that Clinton, who has been isolated by the mounting scandal in recent months, should welcome the suggestions of top Democrats outside his inner circle of advisers.
"These decisions should not be made at the White House, because clearly there have been a lot of bad decisions made there," says Tim Penny, a former Democratic congressman from Minnesota.
However, Clinton lacks confidants in Congress, experts say.
"He has some friends but they are generally outside of politics," says Mr. Panetta. "Being so political, he communicates with everybody, but it doesn't go deeper than that."
"[Clinton] tends to want to do the talking when he meets in groups," he adds. "He's not as good a listener. And when you are dealing with Congress, they like to do the talking."