When Sen. Joseph R. Biden Jr. started a new political fundraising committee three years ago, he turned to a longtime Washington insider for help - the partner of a lobbying firm co-founded by his son.
William Oldaker, a federal lobbyist whom one watchdog group dubbed "the rainmaker," and his associates have held dual roles as insiders for Mr. Biden's political committees and the lobbying firm co-founded by his son R. Hunter Biden.
Since 2005, Mr. Biden's fundraising committee, Unite Our States, and his political campaigns have raised millions of dollars, including at least $115,000 in donations from employees and clients of Mr. Oldaker and his son's lobbying firm, D.C.-based Oldaker, Biden and Belair.
One Chicago law firm specializing in asbestos lawsuits paid the lobbying firm $220,000, while its employees have given Mr. Biden's campaigns and fundraising committee more than $70,000 in donations, Federal Election Commission records show.
Oldaker, Biden and Belair has increased its lobbying revenues from $500,000 in 2002 to $3.5 million last year, according to the Center for Responsive Politics. Since 2005, the firm has received more than $10 million from corporate lobbying clients and political campaigns. Mr. Biden has used Oldaker, Biden and Belair lawyers to provide legal services for his campaigns.
Such entanglements are giving fuel to Republican critics who say Sen. Barack Obama's choice of Mr. Biden as his running mate doesn't square with his frequent criticism of Washington insiders and lobbyists on the campaign trail.
"Biden's ... connections to the special interests that Obama claims to oppose once again proves the freshman senator from Illinois' rhetoric in no way matches his record," said Danny Diaz, spokesman for the Republican National Committee.
Biden spokesman David Wade dismissed the criticism as "Republican spin."
He said Mr. Biden brings "a 35-year record fighting for people when powerful interests have stood in the way of the public interest, whether it's drug companies, oil companies or insurance companies. John McCain has yielded to special interests that have written his campaign platform."
Mr. Wade said his boss has never shown favoritism to anyone, especially his son: "Senator Biden has been as strong a supporter of ethics reform as the Senate has known, and his office follows all ethics laws right down to the letter," he said.
Still, Mr. Oldaker's roles as campaign insider and corporate lobbyist were raising concerns from watchdog groups as far back as 2005, after the nonpartisan Center for Public Integrity dubbed Mr. Oldaker "rainmaker."
The group criticized the fact that he worked as a federal lobbyist while also working as the treasurer for nearly two dozen political campaigns.
Mr. Oldaker did not return telephone messages Thursday.
Political committees on which Mr. Oldaker served as treasurer until 2005 had donated $2 million to politicians, including some of the same elected officials whom his firm was lobbying on behalf of corporate clients, the watchdog group found.
When Mr. Biden launched his political action committee in 2005, Mr. Oldaker served as the custodian of records for Unite Our States, though he no longer works in that capacity.
At least two other Oldaker, Biden and Belair workers have served on Mr. Biden's campaign committees as either treasurer or custodian of records, according to Federal Election Commission filings.
"It's just such a tight little circle of influence," Bill Buzenberg, executive director of the Center for Public Integrity, said Thursday.
"It's an association that works extremely well for corporations and lobbyists, but you have to wonder what the public interest is here," he said.
A big Democratic donor, Mr. Oldaker served as an adviser to President Clinton on bioethics issues.
Formerly a partner at Washington-based Manatt, Phelps and Phillips, another big lobbying and law firm, Mr. Oldaker has donated more than $200,000 mostly to Democrats since 1993, according to the Center for Responsive Politics. He has given $8,600 to Mr. Biden's Senate and presidential campaigns and $3,000 to Unite Our States.
At least one lobbying client at Oldaker, Biden and Belair has been a big backer of the senator from Delaware.
Employees at the Chicago personal injury firm of Cooney and Conway paid Oldaker, Biden and Belair $220,000 in 2005 and 2006 to lobby on tort reform issues. Its employees have given more than $70,000 to Mr. Biden's political campaigns. The firm did not return telephone messages Thursday.
Speaking for an article on the support that prominent lawyers were providing to presidential campaigns, John D. Cooney, a partner at the firm, told the Chicago Daily Law Bulletin that he got to know Mr. Biden in 2004 when the Senate Judiciary Committee sought to pass a bill that Mr. Cooney thought would hurt his clients who suffer from asbestos-related injuries.
The law firm is no longer a client of Oldaker, Biden and Belair.
Employees at the University of Delaware, a former lobbying client, have donated more than $20,000 to Mr. Biden's campaigns.
The Republican National Committee has been hammering away at Hunter Biden's lobbying for days, but it's not clear whether the attacks will resound with voters.
"I don't know that it's going to have that much of an impact because what's really going to drive voters are the major issues like Iraq, the economy and foreign policy," said Robert Olendick, a polling specialist at the University of South Carolina.
"The closer we get to the election, there will be more of a focus on Obama. But if Biden portrays himself as an outsider, then the Biden focus might come in and they'll try to use that as a contradiction against him."
Mr. Biden announced Unite Our States in fall 2005, a little more than a year before beginning his own failed run for the White House. He said the political action committee sought to elect candidates "committed to addressing the challenges facing our country by beginning to unite red and blue states, big cities and small towns, and Americans of all walks of life."
One of the biggest recipients of campaign cash from Mr. Biden's committee has been the Democratic Senatorial Campaign Committee, which has received $65,000 in donations since 2005, FEC records show.