The Democratic National Committee is bracing itself for protests outside its Rules and Bylaws Committee meeting on Saturday in Washington, where the fates of the Florida and Michigan primaries could finally be decided.

Supporters of Senator Hillary Rodham Clinton are organizing to march and then gather on the street outside the panel’s meeting, scheduled for Saturday morning at a hotel in Northwest Washington.

“They’re coming up on buses, they’re taking the train, they’re Metro-ing, they’re coming up with friends,” said Allida Black, a professor at George Washington University and an event organizer. “We’re trying to flood it.”

The Rules and Bylaws Committee is expected to address the primary votes from Michigan and Florida, which moved up their primaries in violation of national party rules. The Clinton campaign has pinned its hopes on the Michigan and Florida votes being added to the totals, giving her a much-needed boost in the final days of the primary campaign.

Besides their goal of pressuring the committee into counting the votes from Florida and Michigan, Mrs. Clinton’s supporters are hoping that an en masse gathering will demonstrate widespread support for her candidacy — and perhaps persuade a superdelegate or two.

Ms. Black is behind the newly formed political action committee, WomenCount, which has been running full-page ads in newspapers for the last two weeks in support of Mrs. Clinton. She said the rally will be staged on a grassy area outside the Marriot – Wardman Park Hotel in the Woodley Park neighborhood in Washington, and that the group has been granted permission to assemble several blocks to the north near the National Zoo for a 10-minute march to the hotel. Jehmu Greene, a former president of Rock the Vote, will address the crowd at the rally.

Public tickets to observe the meeting have already been snapped up, said Stacie Paxton, a spokeswoman for the Democratic National Committee. On Tuesday morning, the Democratic National Committee opened online pre-registration for public seating, and the several hundred tickets disappeared within minutes.

“There’s been overwhelming public interest,” Ms. Paxton said. (C-Span is also expected to broadcast the meeting.)

The members of the public who managed to reserve seats will be able to listen to the proceedings, but not participate. The committee will begin the meeting at 9:30 a.m., listen to oral arguments, and then debate amongst themselves after a lunch break.

On its Web site, the Democratic National Committee has advised the public that “in order to maintain the decorum of the meeting, banners, posters, signs, handouts, and noisemakers of any kind are strictly prohibited.”

If they cannot come to a decision this weekend, the committee refers all outstanding business to the party’s credentials committee.