WASHINGTON – Lobbyist Jack Abramoff and an associate famously collected $82 million in lobbying and public relations fees from six Indian tribes and devoted a lot of their time trying to persuade Republican lawmakers to act on their clients’ behalf.

But Mr. Abramoff didn’t just work with Republicans. He oversaw a team of two dozen lobbyists at the law firm Greenberg Traurig that included many Democrats. Moreover, the campaign contributions that Mr. Abramoff directed from the tribes went to Democratic as well as Republican legislators.

Among the biggest beneficiaries were Capitol Hill’s most powerful Democrats, including Tom Daschle and Harry Reid, the top two Senate Democrats at the time, Rep. Dick Gephardt, then-leader of the House Democrats, and the two lawmakers in charge of raising funds for their Democratic colleagues in both chambers, according to a Washington Post study.

Democrats are hoping to gain political advantage from investigations of Mr. Abramoff’s activities and from the embattled lobbyist’s former ties to House Majority Leader DeLay. Yet, many Democratic lawmakers also benefited from Mr. Abramoff’s political operation, a fact that could hinder the Democrats’ efforts to turn the lobbyist’s troubles into a winning partisan issue.

Democratic lawmakers who responded to inquiries for this article said that any tribal money they received had nothing to do with Mr. Abramoff. They were quick to say they did not know the man.

Federal investigators are examining the millions of dollars in lobbying and public-relations fees that Mr. Abramoff obtained from the tribes. They are also looking into his dealings with members of Congress and their staffs, lawyers involved in the inquiry said.

Most lobbying firms here are bipartisan to give their clients access to key lawmakers of both parties. Mr. Abramoff’s group was no exception. Although he was recognized as a Republican lobbyist who was close to Mr. DeLay and other party leaders, Mr. Abramoff was careful to add at least two Democratic lobbyists to his group during his five years at Greenberg Traurig. By the end, seven of his lobbyists were Democrats.

“Lobbying shops typically direct contributions to both parties because they want contacts on both sides of the aisle,” said David Hart, a public policy professor at George Mason University. According to documents and tribal officials familiar with the Abramoff team’s methods, the lobbyists devised long lists of lawmakers to whom the tribes should donate and then delivered the lists to the tribes. The tribes wrote checks to the recommended campaign committees and in the amounts the lobbyists prescribed. The money went to incumbents or selected candidates in open seats.

Because of the makeup of his team and the composition of Congress, the Abramoff lobbyists channeled most of their clients’ giving to GOP legislators. Senator Burns of Montana, chairman of an appropriations subcommittee that deals frequently with Indian matters, received the largest amount from the tribes as well as from the Greenberg Traurig lobbyists who helped direct those donations: $141,590 from 1999 to 2004.

But Rep. Patrick Kennedy, a Democrat of Rhode Island, ran second with $128,000 in the same period. From 1999 to 2001, he chaired the Democratic Congressional Campaign Committee.

The Indians’ largesse flowed to higher-ranking Democrats as well. Senate Democratic leaders Reid and Daschle each got over $40,000 from the tribes and Abramoff-team lobbyists during the period. Mr. Gephardt took $32,500.

Of the 18 largest recipients of tribe contributions directed by Mr. Abramoff’s group, six, or one-third, were Democrats.