On a lavish, weeklong Caribbean cruise last year, software entrepreneur Warren Trepp wined and dined friends and business partners aboard the 560-foot Seven Seas Navigator.

Among Mr. Trepp's guests on the cruise ship: Rep. Jim Gibbons of Nevada and his family. The two men have enjoyed a long friendship that has been good for both. Mr. Trepp has been a big contributor to Mr. Gibbons's campaigns, and the congressman has used his clout to intervene on behalf of Mr. Trepp's company, according to congressional records, court documents and interviews. The tiny Reno, Nev., company, eTreppid Technologies, has won millions of dollars in classified federal software contracts from the Air Force, U.S. Special Operations Command and the Central Intelligence Agency.

...Mr. Gibbons is in a tight and bitterly fought race (for Governor as the GOP candidate). He held a double-digit lead until two weeks ago, when a cocktail waitress said he accosted her after a night of drinking. Mr. Gibbons has forcefully denied the claim, which is unproven, but details of the case have been page-one news in Nevada, and his lead slipped to six points in a weekend poll.

...Public records show that Mr. Trepp has been a generous supporter of Mr. Gibbons's campaigns. Nevada law prohibits individuals or corporations from giving more than $10,000 to a candidate in a single election cycle. Companies and partnerships that Mr. Trepp incorporated or controls have given almost $100,000 to Mr. Gibbons. These entities, many of which list the same mailing address, gave the maximum amount on the same day last year. Mr. Gibbons said the campaign contributions didn't violate Nevada law because they came through different corporate entities.

...Mr. Gibbons himself touted one earmark in a June 2004 news release. In the release, Mr. Gibbons's office said he "specifically requested" a program that would pay $3 million for eTreppid's automatic target-recognition technology, a computerized technique for picking out objects from a stream of video images.

...In the following year, an email from an eTreppid executive to Mr. Trepp and others at the company described a $1.5 million "plus-up," or earmark, that the company's Washington lobbyist "helped us get through Jim Gibbons."

..."The problem with earmarks is that they don't go through the normal oversight process -- a problem that is much worse in black programs, which have less congressional oversight and obviously no public scrutiny," says Steven Kosiak, a researcher at the Center for Strategic and Budgetary Assessments, a nonpartisan Washington policy group.

...Between 2003 and 2005, Mr. Gibbons repeatedly arranged meetings and demonstrations for eTreppid executives with top Air Force generals, both in Washington and Reno, according to congressional staff and company documents.

On Sept. 25, 2003, the congressman had breakfast with the Air Force vice chief of staff, where he pitched the promise of eTreppid's technology, according to a memo from a Gibbons staff member to an eTreppid executive. Also in September, Mr. Gibbons, in an email to an eTreppid executive, offered to try to set up a meeting with the National Security Agency. It isn't known if the meeting took place.

In May 2004, a lobbyist acting for eTreppid in Washington reported in another email, "Congressman Gibbons certainly came through for eTreppid!" She said Mr. Gibbons secured a $7 million appropriation for the company.

...House records show that in 2004, the lobbyist pushed for eTreppid's interests in the defense-authorization and intelligence bills. Mr. Gibbons served on both of those committees.

...On the Caribbean cruise in March last year, photos taken on board and at the Atlantis casino in the Bahamas show the Gibbons and Trepp families together at dinners and parties. Also on the cruise were actors Patrick Swayze and John O'Hurley, who played the role of J. Peterman in the "Seinfeld" television series. The group flew back to Nevada after the cruise on a chartered Boeing 727 paid for by Mr. Trepp.

Mrs. Gibbons says she helped pay for the trip by giving a $1,654 check to Mr. Trepp's wife and putting $1,508 on her credit card for on-board expenses. An agent for the cruise line estimated the cost of a comparable cruise for a family of three at more than $10,000, excluding airfare.