Step aside. Put down your crab claw.

Here comes Jackie Presser.

The president of the Teamsters Union sticks out a hand the size of a Virginia ham, brightens his eyes and, to a guest he has never met before, fairly purrs.

"How are ya? I've heard a lot of good things about you!"

A huge table decorated with an ice sculpture and covered with cheeses sits in the very center of a ballroom in the Hyatt Regency. Presser makes his entrance and begins a huge circle around the table, slowly, like a barge on a day cruise around Manhattan Island. Union members approach Jackie Presser with their names on their tongues, hands ready for shaking. And Jackie Presser answers:

"How are ya? I've heard a lot of good things about you!"

Presser runs into one of the dozen or so House members who have come to this inaugural reception -- among them Frank Annunzio (D-Ill.), Hamilton Fish (R-N.Y.), Louis Stokes (D-Ohio), Mary Rose Oakar (D-Ohio) and House Minority Leader Robert Michel (R-Ill.). Presser talks with Austin Murphy (D-Pa.) as if Murphy were his only friend in the world. Presser gives it two minutes and then he breaks the huddle.

Murphy beams in admiration as he watches Presser return to his Great Circle Route.

"Jackie's great at working the room. One of the best," Murphy says. "I'm glad he doesn't run against me. Tip O'Neill's high on my list of working the room. Hubert Humphrey was great and, in his own way, Ronnie Reagan does a pretty good job. You gotta come up with a smile, look the other guy in the eye and say something nice, like, 'How are you? Good to see you.' Whatever. That makes for good working-the-room technique, and Jackie's one of the best."

Jackie Presser is an eighth-grade dropout who worked his way up from jukebox salesman to union president wooed by the White House. He succeeded Roy Lee Williams, who resigned in 1983 after he was found guilty of conspiracy to bribe a senator. Presser himself is currently the subject of a federal probe into embezzlement of Teamsters funds, and White House counsel Fred Fielding once cautioned that the administration should keep Presser at "arm's length." But when the Teamsters endorsed Reagan in 1984, as they had in 1980, the White House welcomed the union's support.

"You know," Presser says, "we never really had political parties until I became president. We're just staying in pace with the mainstream of the American worker . . . And we'll keep listening to the heartbeat of the American working man."