House Democratic leaders yesterday moved to put down a broad rank-and-file revolt over a campaign finance bill scheduled for a floor vote Friday by strengthening provisions of the measure aimed at protecting incumbents.

At a closed meeting of the Democratic Caucus yesterday morning, an angry outpouring of complaints eruputed over the campaign financing proposal that House Speaker Thomas S. Foley (D-Wash.) has insisted must be voted on before Congress begins its month-long August recess at the end of this week.

The central complaint, primarily from lawmakers whose states will be most affected by redistricting in 1992, was that the bill's spending limits would affect incumbents who face vigorous challenges in primary and general elections.

Under the leadership bill, House candidates would face a voluntary spending limit of $550,000 per election cycle, including up to $300,000 in a primary. Many lawmakers complained that if they faced a competitive primary, and their opponent did not, the challenger would have far more resources left for the general election campaign.

Rep. Al Swift (D-Wash.), who has spearheaded the effort to pass the bill, said it is likely that the measure would be changed so there would be separate limits for a primary and a general election and that leftover primary funds could not be carried over into a general election.

The chorus of complaints underscored what some lawmakers said was a desire by many Democrats not to pass campaign finance revisions, leaving intact a system with which they are comfortable and that strongly favors incumbents.

"People don't even want to think about competition," one Democrat said.

"The way it's going to work out is nothing is going to pass," another Democrat predicted. "Everyone has their fingers crossed that it will be vetoed by the president. The House doesn't want {campaign finance reform} to happen, the Senate doesn't want it to happen. They just want to get Common Cause and the editorial writers off their backs."

"These guys are paralyzed by the fear of change," said a third Democrat who is active in pushing the package. The lawmaker noted that several Democrats at yesterday's closed-door meeting said their party would be better off without a reform bill because voters do not care about the issue.

In addition to the voluntary spending lid, the measure would place a 50 percent limit on contributions from political action committees and restrict use of so-called soft-money and independent expenditures.