Sen. Barack Obama might boast that he’s on a mission to clean up Washington’s ethics. But the Illinois Democrat and presidential candidate might want first to look in his own camp, where he’d find a veritable hotbed of illicit activity.

[IMGCAP(1)]Campaign spokesman Bill Burton last week told National Journal that press assistant Lauren Thorbjornsen had taken home $250 for winning the Obama campaign’s NCAA hoops pool. Law-and-order readers might have picked up on the fact, though, that office pools actually are illegal. In fact, betting on sports is banned everywhere except Nevada and Atlantic City, N.J., which makes the Obama staffers who participated in the pool outlaws by definition.

Yes, yes, we know that office pools are a staple of workplaces around the country (According to a study by Careerbuilder.com, 19 percent of workers say they participated in such a pool.) But the “everybody’s doing it” defense doesn’t usually work so well.

Obama, who’s a hoops fan himself, won the Senate’s 2007 pool, although it wasn’t clear whether there was money involved, or just glory.

An Obama spokesman would not comment on the matter.

Stay tuned: Next week, HOH hopes to bring you the sordid real-crime tale of staffers for Obama rival Sen. Hillary Rodham Clinton (D-N.Y.) gleefully ripping off those mattress tags that read, “Do not remove under penalty of law.”

HOH: The Contest! Because we know just how competitive Hill types are, and how much you love free T-shirts, HOH is proud to bring you the first installment of an occasional feature, Heard Mentality. We’ll be asking readers to submit their HOH-larious answers to our challenges. Then we’ll print the best of the entries. Your inaugural task: In honor of the Fifth Annual Congressional Blues Festival, come up with the title and as many lyrics as you like for a Congress-themed blues song. Bonus points for anything that rhymes with “302(b).”

The winner will snag not only the glory of having his or her submission run in HOH, but a super-snazzy T-shirt proclaiming the wearer’s witness. And in case that’s not enough incentive, here’s a little extra motivation: Your chances of winning are way better than your odds of winning The New Yorker’s caption contest.

For the blues-song contest, please submit your suggestions by April 21 to hoh@roll call.com, with the subject line “Heard Mentality.” Good luck!

Department of Odd Couples. Rappers and politicos might be celebs in their own circles, but a chance meeting in first-class proves that the two worlds are, well, worlds apart. An HOH tipster spotted former D.C. Mayor Anthony Williams and rapper Christopher Bridges, aka Ludacris, sitting obliviously next to one another on a Saturday morning shuttle from Washington to Boston. The Atlanta-based rapper, who also starred in the movie “Crash,” was unfazed by his proximity to Williams on the US Airways flight from Reagan National Airport to Boston on Saturday morning, the HOH spy says — and apparently, the feeling was mutual.

The pair didn’t exchange a word during the flight, the tipster says. Ludacris, who was wearing a black T-shirt with “F—k the Industry” emblazoned across it, looked a bit flummoxed when a fellow rider reached to shake hands with the Nats-baseball-cap-wearing Williams.

Luda’s disinterest in Williams followed another sighting of everybody’s favorite pundit, Charlie Cook, in the onflight company of a rap star. While sitting next to Cook might be a thrill for most political junkies, his first-class seatmate on a flight from Atlanta to D.C. a few weeks ago — rapper Jay Jenkins, who uses the stage name Young Jeezy —didn’t try to press Cook on his thoughts on the upcoming presidential race.

Called to Duty. Georgia Republican Rep. Paul Broun has been a Member of Congress for less than a year, but he didn’t let his freshman status stop him from schooling fellow lawmakers about the correct way to say the Pledge of Allegiance.

Before leading the House of Representatives in saying the pledge Monday afternoon, Broun took fellow lawmakers, visitors in the gallery, and C-SPAN-watchers to task, lecturing them on the “proper way” to deliver it. According to Broun, it should be said without a comma or break between “one nation” and “under God,” a tipster tells HOH. While many a first-termer might have opted to let fellow pledgers make the nearly ubiquitous error, Broun spokesman John Kennedy says his boss, who served in the Navy, the Marines and the National Guard, believed he had a duty to remind everyone of the right way to say the pledge.

“As a Marine, clearly, he’s had to face a lot more difficult challenges than instructing Members of Congress on the proper way of saying the Pledge of Allegiance,” Kennedy told HOH. “There is, in fact, no comma in that section. So correctly, it’s said, ‘One nation under [God],’ no separation or implied separation between nation and God.”

We trust Broun also has checked on how the Capitol flags are folded.

Briefly Quoted. “The people who work here joke about you can always tell when it’s summertime because you can smell the visitors. And what we mean by that, Mr. President — they stand out there in the high humidity, heat, sweating, and it’s really — there’s no place for them to go.”

— Senate Majority Leader Harry Reid (D-Nev.) bemoaning the lack of gathering spots for tourists in the construction-ridden Capitol and, perhaps, the personal hygiene habits of the visiting hordes.

Mike Lepage of GalleryWatch contributed to this report.

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