Any administration heavies and their spouses worried about a post-Reagan future can rest assured: The music industry awaits. After all, any team able to convert "Jingle Bells" into an anthem celebrating the president and his staff can surely conquer MTV.

"Do your best/Do your best/Work with all your hearts," a group including Ursula Meese, Mary Jane Wick and Barbara Hodel and identified as "Santa's Helpers" sang at last night's Christmas party thrown by public relations mogul and Reagan pal Roy Pfautch. "With Ronald Reagan leading us, we all will do our part."

The revised lyrics to "Have Yourself a Merry Little Christmas" will be left to the imagination.

In addition to providing an evening's nourishment for an assortment of lobbyists and business types, Pfautch's party draws from the old Reagan club and has traditionally been a time for insider jokes -- or as inside as is possible in a room filled with more than 400 people -- and in-house support. Some traditions rarely change, like the presence of a mystery Santa and the convenient scheduling of the event, which usually manages to land on the same date as Attorney General Edwin Meese's birthday.

But in some ways this year was different. William Casey and Malcolm Baldrige, both of whom played Santa Claus in the past, have died. Between two failed Supreme Court choices and an Iran-contra report highly critical of him, Meese has had a particularly rough political year. One Reagan insider and Christmas party regular (Michael Deaver) is currently on trial for perjury, and another (Lyn Nofziger) has been indicted on six counts of violating conflict-of-interest laws. And the president, who unites the crowd even in his absence, has himself been through some trying times recently.

"The last year's been difficult -- terribly difficult -- in fact, I'd almost say terrible," former secretary of agriculture John Block said about the administration. "But I don't think that has to be a sign for how the next year will be."

Deaver didn't attend last night's party at the J.W. Marriott, but Nofziger showed up and stood near the door where he could receive arriving guests.

"You survive them," he said, describing what dark days are like. "You just go about your business. -- Hi, dear," he interrupted himself, turning to a new face. "How are you? -- You have to make the assumption that you're an honest and honorable person and therefore you go about your business. You don't want to embarrass people -- you want to be certain about that. They all tell you you don't, but still you worry about it. The nice thing is there isn't anybody in this room who won't talk to me, and there isn't anybody in Washington who won't return my phone calls."

Having blown out his candle at the privacy of his own table, Meese said he thinks the administration won't have to wait until next year for all its troubles to be far away. "I think the Supreme Court candidate will be very successful," he said of Judge Anthony Kennedy, who is scheduled to begin his confirmation hearings Dec. 14. Meese said despite reports that he opposed Kennedy at the time the president nominated Douglas Ginsburg, Kennedy "was one of my first choices. I've known him for 20 years and he's someone I'm very confident in."

Before welcoming master of ceremonies Wick to the stage, Pfautch described his party as "a big family gathering." One guest offered an alternative description of the guest list: "Everyone who is, was, will be or might be." There were even some last night who speculated that the Democrats had begun to make inroads ("As the election gets closer, Roy's church develops new pews," said lawyer Edward Weidenfeld of his host, who happens to be a minister as well as everything else) but others insisted that a non-Republican face was hard to find.

Circulating through the crowd were any number of political consultants, including Lee Atwater, Ed Rollins and Roger Stone. In general, praise was obligatory for the performances by the Republican presidential candidates in Tuesday night's debate, but some were less than pleased with party members who are condemning Reagan's support of the treaty he is expected to sign at next week's summit with Soviet leader Mikhail Gorbachev.

"Anyone who criticizes Ronald Reagan for being soft either doesn't know Ronald Reagan," said Maureen Reagan, "or is trying to make political hay for themselves, and I don't think that's how you do it." Of the GOP candidates she said, "I would suggest they read the agreement, make their comments and let the president get on running the country."

Guests were required to bring toys for the Marine Corps Toys for Tots drive, in return for which they got: a sit-down dinner ending with a chocolate Santa's boot filled with mousse; entertainment by strolling carolers; and the opportunity to hear Sen. Ted Stevens recite "'Twas the Night Before Christmas." The birthday boy/attorney general received his cake from the mystery Santa, who turned out to be Agriculture Secretary Richard Lyng. "I'm glad you still believe in Santa," Lyng said to Meese. "As a matter of fact, your letter this year was the best ever.