Yesterday, CREW filed an ethics complaint against Senator John McCain (R-AZ) for failing to disclose his gambling winnings.  That move has generated a good deal of media coverage.

The Hill:

The Senate Ethics Committee should look into whether John McCain violated federal laws by failing to list gambling winnings on his Senate financial disclosure forms, according to a watchdog group. 

The request by the left-leaning Citizens for Responsibility and Ethics in Washington (CREW) cites several media reports describing McCain as an avid, high-stakes gambler. The group questions why the Arizona senator has not included any gambling winnings on his disclosure forms.

"The Crypt" at Politico.com:

It's no secret that McCain likes to shoot craps, but his campaign told Politico Thursday afternoon that McCain had no gambling winnings in 2006 or 2007. The CREW complaint cites a 2007 weekend in Las Vegas gambling at MGM among the reported incidents in which McCain walked away a winner.

"He had no gambling winnings in 2006 or 2007," McCain spokesman Brian Rogers said in an e-mail. "If he had, they would have been disclosed on his tax returns."

CREW also points to a New York Times report about a McCain visit to Foxwoods Casino in 2000 in which he won money but did not report it on his 2001 disclosure forms.

The Washington Post:

The CREW complaint, however, provides a window into McCain's gambling nature; assuming he abides by all Senate and federal tax laws, McCain's not much of a winner at the craps table.

Under Senate rules, all gambling winnings would be treated the same way as pension plans, book royalties, or other winnings from competitions such as lotteries that are open to the public. They are considered "earned income."

So, under Senate rules, at the end of each year, McCain was required to tally up those gambling trips and determine if he netted at least $200. If he had, he was required to report such winnings on his disclosure forms.

Federal tax law is even more strict: "All gambling winnings must be reported irrespective as to whether any portion thereof is subject to withholding. In addition, you may be required to pay an estimated tax on your gambling winnings."

(For anyone who's ever spent a weekend in Las Vegas, this would appear to be one of the most loosely enforced tax rules ever. However, there are plenty of online guides to explain how McCain, or even once-a-year gamblers, are supposed to report wins and losses while legally gambling.)