WASHINGTON — With the House poised to take up a major ethics bill, Republican leaders have deleted a provision that would, for the first time, regulate the collection of “political intelligence” from political insiders for the use of hedge funds, mutual funds and other investors.

House Democrats protested the change on Wednesday, but said they would still vote for the bill — to ban insider trading by members of Congress — when it reached the House floor on Thursday. A version of the bill that the Senate passed last week would require “political intelligence consultants” to disclose their activities and register as lobbyists do.

Representative Louise M. Slaughter, Democrat of New York, said lawmakers and the public needed to know more about the activities of these professionals, who she said “glean information from members of Congress and staff and sell it to clients who make a lot of money off it.”

Ms. Slaughter said many people on Wall Street and in the political intelligence business were lobbying against the registration requirement, which could force investment advisers to disclose the clients for whom they did policy research.