The Jack Abramoff scandal snared another Congressional staffer Monday, as John Albaugh, the former chief of staff to ex-Rep. Ernest Istook (R-Okla.), pleaded guilty in U.S. District Court for the District of Columbia to one count of conspiracy to defraud the House of Representatives.

Albaugh, 41, had worked for Istook since he was first elected in 1993, becoming his chief of staff in 1998 and remaining so until Istook left office in January 2007.

According to the documents filed by the Justice Department, Albaugh was part of a conspiracy “to benefit himself and/or Representative 4 by using and agreeing to use his official position by performing and agreeing to perform official acts in return for a stream of things of value benefiting himself and/or Representative 4.”

Representative 4 is not named in the document but is described as the Member whom Albaugh worked for.

“Mr. Albaugh decided to accept the government’s proposal and move on with his life,” said Albaugh’s attorney, Jeffrey Jacobovitz, a partner in D.C.’s Schiff Hardin. “He deeply regrets and accepts full responsibility for his involvement in these matters and their impact upon his family and the community.”

Albaugh will be sentenced by U.S. District Judge Ellen Huvelle on Sept. 17. He faces anywhere from 18 to 24 months, according to federal sentencing guidelines, but the government could ask for less depending on the extent of his cooperation. He currently lives in South Carolina, where he works in real estate development.

Asked whether Istook was implicated in the conspiracy or whether his client intended to provide information that would implicate others, Jacobovitz said, “I cannot say anything about cooperation.”

But in a statement, Istook, who is currently a distinguished fellow at the Heritage Foundation in Washington, said he was not a target of the Albaugh probe.

“I am as surprised and as shocked as anyone,” said the Istook statement. “I have not seen the charges and I have no information about them. I have met with the FBI. They did not share any details about the case, but they told me I am not a target of their investigation. I will continue to cooperate with them fully.”

After 14 years in Congress, Istook opted not to run for re-election in 2006, instead making an unsuccessful bid that year in the Oklahoma gubernatorial race.

During his tenure in the House, Istook received nearly $30,000 in campaign contributions from lobbyist Jack Abramoff and his associates, but he donated those funds to charities before retiring. In addition, his campaign repaid thousands of dollars in late 2005 for the use of concert tickets provided by Abramoff.

According to the Justice Department, Albaugh conspired with a lobbyist who had previously worked for a House Member, had been a staffer on the Senate Judiciary Committee and had been executive director of a “political party Caucus.”

That résumé dovetails with Abramoff associate Kevin Ring, who worked for Rep. John Doolittle (R-Calif.) in the House, was a staffer on the Senate Judiciary Committee and was the director of the Conservative Action Team in the House.

The charging document alleges that in March 2003, at Albaugh’s suggestion, Istook called Abramoff to thank him “in advance for use of one of his FedEx Field suites for an upcoming fundraising event. During that call [Istook] also asked which particular projects [Abramoff’s clients] wanted in the transportation bill.”

Abramoff told the lobbyists working for him to “make sure we load up our entire Christmas list,” the Justice Department alleges.

With Istook as chairman of the Appropriations Subcommittee on Transportation, Treasury and Independent Agencies, Albaugh “agreed to ensure that [Abramoff clients] received more than $4 million in a Subcommittee draft of the transportation appropriations bill.”

According to court documents, when Istook became an Appropriations cardinal, Ring received an e-mail from a fellow unnamed lobbyist, stating: “[T]hat’s good for us!! Hello Albaugh.”

Albaugh is accused of repeatedly accepting tickets to sporting events and concerts and free meals without disclosing these gifts on his financial disclosure forms. Among the events he received tickets to were NFL games, a professional horse show at the Patriot Center in Fairfax, Va., children’s musical group The Wiggles, and a Disney on Ice show.

The charges indicate that Ring was orchestrating the contacts with Albaugh and providing the meals and tickets, and presenting the legislative requests to Albaugh.

According to the charging document, Istook benefited from a February 2003 fundraiser that Abramoff and his associates held at Abramoff’s former restaurant, Signatures.

The documents state that while Albaugh solicited this dinner, Istook’s campaign committee didn’t reimburse Ring, or Ring’s firm at the time, Greenberg Traurig, or the restaurant for the cost of the event, or file an in-kind contribution with the Federal Election Commission.

Following that fundraising event, Istook called Abramoff at Albaugh’s suggestion asking Abramoff “which particular projects [Greenberg Traurig’s] clients wanted in the transportation bill,” according to court documents.

According to court documents, during one such event — an “American Idol” concert at the MCI Center in July 2003 — Albaugh, Istook and Ring “discussed” procuring a $4.183 million earmark for one of the lobbyist’s clients.

Among Ring’s clients at the time was Carter County, Mont., which paid Greenberg Traurig $60,000 in 2003, and whose federal disclosure forms listed its lobbying issue as “secure federal funding for highway project.”

In the report accompanying the House version of the fiscal 2004 Transportation and Treasury spending bill, there is one item that matches that amount: under the National Scenic Byways Program, Montana State Route 323 from Alzada, Mont., to Ekalaka, Mont., would receive $4.183 million. The project ultimately received $3.5 million.

Abramoff, who pleaded guilty on Jan. 4, 2006, to separate charges of tax evasion, fraud and conspiracy to bribe public officials, has not been sentenced on those charges because he continues to cooperate with federal investigators.

He is serving a five-and-a-half-year sentence at a minimum security prison in Cumberland, Md., for his role in a separate fraud case involving Florida-based SunCruz Casino.

Paul Singer contributed to this report.