Something smelled rotten in Denmark, er, the Senate on Tuesday — and the foul odor was so awful that some Senators even fled for a place where they could breathe easier.

[IMGCAP(1)]Members, staffers and visitors who entered the Senate side of the Capitol on Tuesday morning were quickly overtaken by a fetid smell that some likened to a sewer. The rancid stench was so pungent that when it came time to hold their weekly caucus lunch, Democratic Senators said “smell ya later— to the chamber and headed for the Capitol Visitor Center. Senate Majority Leader Harry Reid even commented on the miserable musk, telling reporters after the lunch ended: “As you know, our room smelled today so we had to leave.—

Seeking the source of the stench, a reporter with a nose for the truth (ba-dum!) asked the Nevada Democrat where he believed it originated.

“I have some ideas,— Reid said. “But I’m not going to tell you.—

Actually, it turns out that water was to blame. The insulation in one of the Capitol’s air handling units (which circulates air inside the building) had somehow gotten wet, according to Architect of the Capitol spokeswoman Eva Malecki. And when that insulation gets wet, it emits the sewer-like odor that countless Senate denizens smelled Tuesday.

The AOC responded by turning the unit off and cleaning it, Malecki added.

Now the halls of the Senate are filled with the usual aroma — that of stalled legislation.

Getting in the Saddle. Between President Barack Obama’s inauguration and a whole lot of bills being introduced, 2009 was a huge year for celebrity visits to Capitol Hill.

And slowly but surely, the famous folk are trickling into the Congressional halls again in 2010.

Case in point: Actresses Kelly Carlson (“Nip/Tuck—) and Wendie Malick (“Just Shoot Me—) joined Sen. Mary Landrieu (D-La.) and Rep. Ed Whitfield (R-Ky.) at a press conference Tuesday sponsored by the Humane Society of the United States to advocate for legislation outlawing horse slaughter and banning the shipment of the animals to foreign slaughter plants.

Malick and Carlson (who has dyed her trademark platinum blonde hair to dark brown, “Nip/Tuck— fans) said their love of horses led them to advocate for the animals. While there are no operational horse slaughter plants in the U.S., tens of thousands of horses are trucked for thousands of miles, under poor conditions, to facilities in Mexico and Canada, said Wayne Pacelle, president of the Humane Society.

Malick was brought to tears during the event when Pacelle played a video of the horses being slaughtered.

“Most people don’t watch them because they’re so disturbing,— Carlson said of videos like the one shown. “And that’s kind of the point. … It is horrible and horrendous.—

Franken’s Parting Words. Sen. Al Franken might have a reputation for being a bit prickly, but clearly, the teenagers of Capitol Hill have taken a shine to him. The Senate pages invited the Minnesota Democrat to their page graduation ceremony Friday, HOH hears, where he was the only Senator in attendance other than the chamber’s leaders.

Franken, with his affable wife, Franni, at his side, watched the ceremony and shared a few words of advice and encouragement with the youngsters.

“It was a nice send-off,— Franken spokeswoman Jess McIntosh says. “He told them how much he appreciates all the work they did running around for him and the other Senators.—

We wonder whether Franken’s advice to the kiddos might have included the “daily affirmation— made famous by his 12-stepping “Saturday Night Live— character Stuart Smalley: “You’re good enough, smart enough, and doggone it, people like you.—

Coleman’s Back. Former Sen. Norm Coleman (R-Minn.) announced (via Facebook) this week that he won’t run for governor of his home state, but don’t think he’s just disappeared off the face of the earth. HOH spies reported a few sightings of Coleman around Washington on Tuesday.

One tipster saw the Minnesota Republican on a flight to Washington from Minneapolis. Coleman was reading the Minneapolis Star-Tribune, our spy says (way to promote the hometown paper!), and another saw him later that morning, looking very much the Everyman.

Coleman was carrying a suitcase and riding the Metro, our tipster says, and he appeared to be exiting at the Capitol South Metro stop.

We couldn’t reach Coleman to find out why he was prowling around his old stomping grounds, but with whispers back home that he could rethink his decision to stay out of the gubernatorial race, it sure looks like he hasn’t lost his taste for politics yet.

Put Your Money Where the Prez’s Mouth Is. Here’s a way to make the State of the Union address a little more interesting.

Paddy Power, the Irish bookmakers that have set odds on everything from who will run for president to when Fox News will fire new analyst Sarah Palin, announced odds on tonight’s address, from its length to the color of President Barack Obama’s tie to the first cliché included in the speech.

The bookies think current events will prevail, setting 4-1 odds that “health care reform— will be uttered first. There are 12-1 odds that Obama will say, “as I stand here today,— “fundamental belief,— “defining moment— and “God bless America— first, and 14-1 odds on “Let me be clear,— “politics of hope,— “common purpose— and “war on terror— (a SOTU favorite of Obama’s presidential predecessor).

As for phrases that he’s unlikely to say? There are 250-1 odds that Obama will announce, “I won’t seek re-election,— and 500-1 odds that he’ll say, “Always bet on black.— A little gambler (and, um, racist) humor there?

Fashion-wise, the bookies don’t expect Obama to get creative, setting 11-10 odds that he’ll sport a red tie and 6-4 odds that he’ll wear blue. They do think, however, the speech will last less than an hour, setting 9-4 odds that Obama will speak between 51.1 and 53 minutes and 11-4 odds that he’ll speak between 53.1 and 55 minutes.

Overheard on the Hill. “Jesus came to me in a dream and told me to run for #INSEN seat. Hope this doesn’t turn out like the time he told me to punch that cop.—

— A Tuesday Twitter post from Pence4Prez, an obviously fake (and often unprintably racy) account purporting to be that of Rep. Mike Pence (R-Ind.).

Submit your hot tips, juicy gossip or comments here.

Can’t get enough HOH? Get a midday dose of fun and gossip with HOH’s One-Minute Recess, delivered to your inbox daily. Sign up here — because everyone deserves more recess.