THE problem with Washington, according to Sen. Russell Feingold, is too much free crumb cake. Every day, explains the Wisconsin Democrat, he receives a handful of gifts from special interest groups - especially those with business pending in Congress. In addition to crumb cake, Senator Feingold has been wooed with books, CDs, peanut brittle, spark plugs, cuff links, bratwurst, denture cream, and a ceramic milk jug. Last year, the National Rifle Association sent the senator a cookbook. To Feingold, free gifts, meals, and trips perpetuate a ''circle of influence'' in Washington that skews policy debates and frustrates voters. Increasingly, his colleagues appear to agree: The Senate recently voted to limit the booty its members can accept, beginning next year. The House may soon follow suit, as GOP leaders now plan to bring sweeping anti-lobbyist legislation to the floor before the end of the year. Welcome to the post-Packwood Congress. Stung by the lame-duck Oregon senator's diary depictions of cozy dealings with lobbyists, lawmakers are eager to put their ethical house in order. Thanks to the Senate's actions, says Rep. Chris Shays (R) of Connecticut, the House should consider gift and lobby reform within six weeks ''without the usual divisive confrontations'' that have accompanied past debates. In the end, says Feingold, these efforts really could make Washington a more upright place. ''By themselves, gifts and meals are not sufficient to corrupt the whole system,'' he says. ''But they create a psychological feeling that you are obliged. Somebody might not even be aware of it, but I think it does have that effect.'' During his 1992 campaign, Feingold vowed not to take any gift whatsoever from a lobbyist. When he goes to dinner, he pays his own way. And at receptions, he accepts nothing more than a glass of ice water. Each of the 1,200 presents his office has received has been logged, tossed into a cardboard box, and donated to charity. Since arriving in Washington in 1993, Feingold says he has come to understand the peculiar Washington lifestyle based on favors. The lure of gifts and swanky receptions, he says, induces some members of Congress to spend substantial amounts of time hobnobbing with ''folks who have an agenda.'' Loose lobbyist laws The Senate passed a gift-limiting resolution last July, at the same time it passed a bill which would tighten the currently loose laws governing who most register as a lobbyist. Under the Senate's new rules members will be barred from accepting anything worth more than $50, and no more than $100 per year in gifts from any one source. The measure also prevents members from accepting travel and accommodations for charity events with strong recreational components, like celebrity golf tournaments. When the rules take effect next year, many of the lavish gifts will disappear. This year, Feingold has received a ''pile'' of steaks, a solid-gold letter opener, several designer silk ties, and a six-inch Waterford crystal statuette of the Washington Monument. But small gifts under $10 will not be limited at all, and Feingold says the resolution leaves some wiggle room for any member who is determined to game the system. ''Under the new rules, you would have to spend an inordinate amount of time trying to arrange things, but it could still be done,'' he says. ''If you were determined to accept every gift, and tried to go to all the things you were invited to, you'd never have to pay your own way.'' During the gift-ban debate in July, Feingold read a list of invitations received by one of his staff members in one week: the Washington Tennis Classic on Monday, a concert by Hootie and the Blowfish on Tuesday, a screening of the movie ''Don Juan DeMarco'' on Thursday, and a Rus-sian vodka tasting on Friday. ''Everybody [in Washington] says that these are little trivial things. But when you get here, you realize that these things aren't trivial. Where I come from, if a family goes to a showing of ''Don Juan DeMarco,'' which nobody else has seen yet, and has dinner and cocktails, that wouldn't just be the highlight of the week, it'd be the highlight of the month, or possibly of the year.'' List of gripes The issue of lobby reform ranks high on the list of gripes most Americans have about Congress, and members from both parties are taking note. The Senate measure, spearheaded by Michigan's Carl Levin and Minnesota's Paul Wellstone, was aided by Feingold and Republicans William Cohen of Maine, and John McCain of Arizona. In the House, the measure's principal sponsor is Connecticut Republican Christopher Shays. Until recently House GOP leaders had been reluctant to consider the lobby reform issue until next year, preferring to concentrate on big-ticket budget-balancing instead. That's changed in recent days due to pressure from GOP freshman and critical Democrats. The House in fact passed legislation that would have tightened lobbyist registration and banned most gifts last year, in the waning months of Democratic control. That bill stalled in conference with the Senate, and eventually fell victim to preelection political wrangling. If few lawmakers hold to such strict no-gift policy, the new rules would certainly persuade members to decline most gifts. One of the beneficiaries would be D.C. Central Kitchen, a six-year-old relief organization that collects food and goods from Capitol Hill events and distributes them to underprivileged Washingtonians. For three years, says Chapman Todd, D.C. Kitchen's associated director, they have been the principal recipient of Feingold's trove. The food is always useful, he says, as are the numerous T-shirts the senator receives, even if they do carry slogans like ''No Tax Cuts.'' But Mr. Todd says many of these gifts (which were, of course, designed to grab the attention of lawmakers) are not even suitable for giving away. In fact, he says, his office has become a veritable museum of useless presents. ''On my desk there's a hard hat from a Milwaukee construction company with the senator's name on it,'' Todd says. ''I don't know if they expected him to wear it around the office or what. I just don't get it.''