Dianne Feinstein, fresh in from the California gubernatorial race for last night's big summer Democratic fund-raising dinner, was chatting with reporters about how the budget deficit has caused Americans "to start to realize that the Republicans aren't the panacea," when up rushed Rep. Beryl Anthony Jr. (Ark.), chairman of the Democratic Congressional Campaign Committee.

He was delighted that Feinstein was there in the great hall of the National Building Museum downtown -- a bright spot in an otherwise somewhat low-key, business-suited crowd of roughly 700 overheated politicians, lobbyists and party loyalists -- and immediately took her in tow to introduce her around. "She'll be the next governor of California," said House Speaker Thomas S. Foley (Wash.), after the two had talked animatedly at a reception before the dinner.

In his dinner speech, former Democratic National Committee chairman Charles T. Manatt noted that the former San Francisco mayor likes it pronounced Fein-STINE, not STEEN, and had once, when visiting New York Mayor Ed Koch persisted in mispronouncing it, warned him in public that she might begin mispronouncing his name in a way that would raise high the roof beams.

That was the evening's only joke, unless you counted Foley's observation concerning the menu (herb-roasted flank steak, cold lobster and "medley of blanched and chilled vegetables") that "I'm not the veggie type."

What is it with the Democrats? At last year's summer party -- the first ever -- they had the hull of a sinking ship in the middle of the room, for reasons that never were completely made clear.

This year, the program consisted of roughly 15 minutes of mostly inaudible speeches by Foley and other members of the Democratic leadership in the House, followed immediately by Jason D. Williams and his band from El Dorado, Ark., who, as Anthony put it, "is cheap." He was also loud, and as soon as he began playing the room suddenly began to empty.

"Soon as that guy hit the keyboard, whoa! Time to go!" said one guest, fleeing down the street.

Yet the evening was a success in other ways. For one thing, at $1,000 a head plus additional contributions, Anthony's staff estimated that it raised $400,000 for the party's war chest. Coming just after a similar affair Monday night in Los Angeles with a $650,000 gate, the dinner made it a million-dollar week for the Democrats.

And the party chieftains were cautiously testing their advantages on the heels of President Bush's recent admission that "tax revenue increases" must be included in an overall deficit reduction package, and the administration's revelation Monday that the 1991 deficit had been significantly underestimated.

"The party's over," said Anthony at the reception. "The economic reality is here." He speculated that Bush, in an effort to "get his economic house in order" before the 1992 presidential election, had "absolutely cut the knees off" his own party's congressional candidates this year with his reversal on taxes and deficit revelations. "He looked," said Anthony, "and said, 'Hey guys, I'm saving myself, you swim on your own.' "

House Majority Leader Richard A. Gephardt (Mo.) disagreed with this idea. "You can't read all that into it," he said. "The economy may or may not be good in 1992, and I just don't know how that affects the election. I think we can win in both '90 and '92."

And Foley, asked about the advantages that Bush has handed the Democrats, indicated he wasn't so sure they really were advantages. But "Democratic candidates are establishing strong records on their own behalf," he said, and don't need any gifts from the president.

Feinstein told another guest at the reception that in California, anyway, "we do have a chance to win this, if we can put it together. I remember being 18 points down!" Democratic success in California is important, Foley noted in his dinner speech, because the state's population has grown so huge that in 1992 one of every eight members of the House will be from there.

Rep. Tom McMillen (Md.), summing up the feelings of many last night, said that the Republicans are finally having to face economic realities. He said that House Democrats "are the ones who have to make the tough decisions, but now the Republicans really have to be 50 percent partners in this."

Also attending last night were former DNC treasurer Peter G. Kelly and Reps. Steny Hoyer (Md.), Dan Rostenkowski (Ill.), John D. Dingell (Mich.), David E. Bonior (Mich.); and Vic Fazio (Calif.).