Rosie, Trey, Tim, Nigel, Jess. … It’s OK if we call you by your first names, right?

Capitol Hill is so overrun with celebrities at the moment that our eyes are practically aching from the collective starriness. Blame it on the upcoming White House Correspondents’ Dinner, or the lure of Washington’s spring (well, given the dreary weather, you can scratch that one) — whatever the reason, famous faces are easier to find around the Capitol than inappropriately dressed interns.

[IMGCAP(1)]That was comedian Rosie O’Donnell, chatting on Wednesday with new best pal Sen. Mary Landrieu (D-La.). And in other scenes from Capitol Hill star-gazing on Wednesday: look, it’s Nigel Barker, the hunky photographer from hit show “America’s Next Top Model—! Oh, and there’s fashion expert Tim Gunn, and Phish frontman Trey Anastasio … and — this just in — we hear Jessica Alba was slated to show at a film screening Wednesday night at the Capitol Visitor Center (don’t worry if you missed her, she’s expected at an event on the Hill today, too).

Whew.

We’ll get to the other famous visitors in a bit, but first the rundown on Rosie, who stayed in the limelight nearly all day with Landrieu. The pair (we’ll call them RoMa) were joined at the hip, promoting legislation introduced by the Louisiana Democrat that encourages college graduates to mentor foster children.

[IMGCAP(2)]RoMa first appeared together at a morning press conference, then made a joint afternoon appearance on MSNBC and even screened O’Donnell’s film about foster care, “America,— at the CVC in the evening.

At the press conference, Landrieu called O’Donnell “the star of this program, the real star who’s here.— But O’Donnell admitted she had butterflies about visiting Capitol Hill.

“I feel a little nervous, like there should be a scandal attached,— O’Donnell said. “But I swear I didn’t do anything.—

America’s Next Top (Congressional) Model. Who knew Rep. Nita Lowey was such a fashion horse?

The New York Democrat’s wardrobe has the approval of “America’s Next Top Model— judge Nigel Barker, who interviewed Lowey on Wednesday for a documentary he’s filming with the Elizabeth Glaser Pediatric AIDS Foundation.

Barker recalled to HOH that before the interview, Lowey asked the crew not to film her tennis shoes, which she feared weren’t especially fashion-forward.

But Barker disagreed, telling Lowey that “they look like Prada.—

“That was all the rage in Europe,— he said of the all-black shoes, adding that Lowey can bring the look to Congress.

Barker’s film, set for a September release, highlights the successes of the fight against HIV and AIDS while also studying the future of the battle. Barker recently spent two weeks filming in Tanzania.

Barker interviewed Lowey, he noted, because she helped oversee the ultimately successful expansion of the President’s Emergency Plan for AIDS Relief.

“She’s a very down-to-earth, maternal lady,— Barker said. “When I was speaking with her, I felt like I was talking to my mum.—

Lowey offered similar praise.

“Congresswoman Lowey was impressed with Nigel’s passion and activism for eradicating pediatric AIDS,— spokesman Matthew Dennis told HOH. “And she was especially happy to get his seal of approval on her shoes.—

HOH notes Barker wasn’t the only reality television fashionista cutting a stylish figure on Capitol Hill on Wednesday.

Several HOH spies reported seeing “Project Runway— star Tim Gunn and the show’s season-five winner Leanne Marshall as they lobbied for intellectual property legislation.

Queens for a Night. If there’s one surefire way to get people to show up at a fundraiser, it’s to offer plenty of food.

And nobody does that better than Rep. Gary Ackerman.

[IMGCAP(3)]The New York Democrat hosted his annual “Real Real 100% Imported From New York Deli Fundraiser (The Whole Schmeer!)— at the Sewall-Belmont House on Tuesday night, treating Members and guests to an array of Big Apple delicacies brought to the nation’s capital by Ben’s Best Deli on Queens Boulevard in Rego Park, N.Y.

[IMGCAP(3)]While pastrami was the most popular menu item of the night, deli workers also dished out classics including matzo ball soup, knishes, chopped liver, stuffed cabbage, corned beef, rye bread and hot dogs from a cart.

Plenty of VIPs showed up for the big feed: HOH spotted singer Carole King dining alongside New York Democrats (Sen. Charles Schumer and Reps. Carolyn Maloney and Charlie Rangel). Several other Members stopped by the soiree, including House Majority Leader Steny Hoyer (D-Md.).

History Lessons. Judging from Congress’ abysmally low approval ratings, people blame the institution for all kinds of horrendous things. But the House historian wants to remind people of one of Congress’ creations that’s proved to be wildly popular, particularly with the ladies: Mother’s Day.

House Historian Robert Remini sent out a notice on Wednesday reminding Hill denizens that while former President Woodrow Wilson often gets credit for establishing Mother’s Day, it actually all began in the House, thank you very much.

The holiday was instituted in May 1914, when Rep. James Heflin (D-Ala.) introduced H.J.Res. 263: “Whereas the service rendered the United States by the American mother is the greatest source of the country’s strength and inspiration … Therefore be it … Resolved, that the second Sunday in May shall hereafter be designated and known as Mother’s Day, and it shall be the duty of the President to require its observances as provided in this resolution.—

The Senate approved the measure later in the day.

And since we know Remini isn’t going to forget Mother’s Day (and have to rush-deliver flowers last minute like many of the rest of us), HOH checked in on him to see how he plans to mark the occasion himself. A spokesman tells us he’ll be spending the day with his wife, Ruth, and their son in Illinois, and Ruth will be expecting a phone call from the couple’s two daughters. The Reminis have been married since 1948.

Now that’s some history.

Gone Phishin’. What could compel a jam-band rocker to don a suit? Phish lead singer Trey Anastasio was spotted making the rounds on Capitol Hill on Wednesday, dressed to impress in a surprisingly conservative suit-and-tie combo.

The musician visited Sens. Dick Durbin (D-Ill.) and Ben Nelson (D-Neb.), along with the leadership of the National Association of Drug Court Professionals to talk about drug courts and rehabilitation for addicts. Anastasio completed a drug court program, which consists of court-supervised testing and check-ins, in 2007 after pleading guilty to a felony drug charge when he was found with heroin and prescription drugs.

The NADCP was slated to give Nelson and Durbin awards Wednesday night at an event on Capitol Hill, a spokesman tells HOH.

Anastasio, we’re told, went relatively incognito during his Congressional visit, but he was friendly and happily posed for pictures when spotted by fans.

Great Expectations. Pregnant ladies, coming through!

About half a dozen expectant mothers — some who looked thisclose to giving birth — attended a House Oversight and Government Reform Committee hearing on Wednesday. The moms-to-be were all federal employees there to support legislation to give government workers four weeks of paid leave after the birth or adoption of a new baby.

The women posed for pictures with the bill’s sponsor, Rep. Carolyn Maloney (D-N.Y.), but mostly sat quietly in the audience.

“They’re expecting action, and I hope Congress will be able to deliver,— Maloney deadpanned.

The committee ultimately passed the bill by voice vote; no word whether supporters celebrated with ice cream and pickles afterward.

Geof Koss of CongressNow and Jude O. Marfil contributed to this report.

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