If the rumors scuttling around Denver that Bruce Springsteen will perform at Invesco Field on Thursday night prove untrue, there could be a backup plan in the works.

[IMGCAP(1)]Rocker-slash-Congressman Joe Crowley has been dusting off his best Boss act, HOH hears, putting in a mean guitar-and- vocals turn at a Sunday

night party with a Springsteen cover band. The New York Democrat took to the stage at a party honoring the Iowa delegation at Denver’s Celtic Tavern, spies say. Crowley found out the B Street Band, a cover band, was slated to play the party, and asked organizers if he could drop by. He played four songs with the band, including classics “Thunder Road” and “Sherry Darling.”

Crowley’s love for Springsteen is well-known: A YouTube.com clip of the Congressman playing a Springsteen tune created a sensation among Hill aides last year, and he’s even professed to want to be the Boss.

Josh Alkin, a lobbyist for Major League Baseball, also took a turn with the band on Sunday, playing lead guitar and vocals for a rendition of “Atlantic City,” spies say.

HOH wonders if Crowley has Thursday night plans. …

Hillary Happy Hour Gets Ethics Nod. The Democratic National Convention might be the ultimate party for supporters of Sen. Barack Obama (D-Ill.), but for loyal fans of his one-time rival Sen. Hillary Rodham Clinton, the whole affair is just a lousy reminder of their tough loss. But it seems somebody in Denver still wanted to throw the New York Democrat a party: Republicans!

The Republican National Committee — in Denver to do counter-operative type-things — was set to hold a “Happy Hour for Hillary” on Monday night, part of the GOP’s plan to win over those unhappy Clinton folks, spokesman Alex Conant told HOH.

“I think it’s clear that there’s a lot of Hillary Clinton supporters at the convention, and so we thought it would be a good opportunity to reach out to them,” Conant said. “On top of that, I think that we want to have fun. This will be a fun event to bring people together, to recognize all of Hillary Clinton’s accomplishments and the problems with Barack Obama’s candidacy.”

Throwing a party for Clinton is sort of tricky, since ethics rules technically prohibit groups from hosting events honoring Members. But political law expert Ken Gross told HOH that the Hillary happy hour likely doesn’t fall under those rules, since it’s obvious that the actual goal is to promote Sen. John McCain’s candidacy.

“Of course, I don’t think Hillary Clinton is coming to this,” joked Gross, a partner at the law firm Skadden, Arps, Slate, Meagher & Flom. “As long as they fell short of literally honoring her … there’s nothing in the rules that can prevent them.”

Dissing DiFi. Democrats might be trying to be all about the unity these days, but female-lawmaker solidarity apparently didn’t stop Rep. Loretta Sanchez (D-Calif.) from taking a little swipe at a fellow Member of Congress.

Sanchez was in Denver on Monday talking to a group of fresh-faced high school and college-aged women about women in leadership — the assembled ladies won a contest for future leaders sponsored by Lifetime Networks, Cosmogirl magazine and the nonprofit campaign Declare Yourself. After Sanchez’s frank talk (she encouraged them to run for office), during the question-and-answer session, one of the young women praised her for being so “spicy,” unlike other women in public office who seem more buttoned-up.

Sanchez agreed that her style sometimes lands her in trouble. “People say I’m too sexy or too spicy or too direct, but it works for me,” she said.

She went on to relate a story about when she first decided to run for her House seat — some advisers suggested she tone down her image. “They said, ‘we have to frump you up,’” she said. But neither Sanchez nor her husband would hear of it. “My husband said ‘I do not want her looking like Dianne Feinstein,’” the Democratic Senator.

Ouch!

Her point seemed to be that a woman seeking office should stay true to herself, not to specifically to diss her fellow Californian’s more formal style. And Feinstein, who is nursing a broken ankle, isn’t even Denver to defend herself.

Like the ‘Real World.’ It’s a Senate slumber party! Or at least a Senate hotel. Most of the Democratic Senators are sharing the same hotel in the Mile High City, HOH hears. Arrangements made by the Democratic Senatorial Campaign Committee are sure to foster camaraderie among the visiting Senators.

We won’t say which posh hotel they’re staying in (for safety reasons, natch), and there’s been no word so far about late-night pillow fights and pajama parties. Still, HOH hears that some Senators are enjoying sharing a hotel, since it means spending some rare hang-out time with colleagues away from usual Senate business.

On the Senate Democrats’ agenda tonight: short-sheeting Sen. Daniel Akaka’s (Hawaii) bedsheets.

Introducing He Who Needs No Introduction. Three guesses who Sheldon Silver, the New York state Speaker, was talking about during a Monday breakfast for the Empire State delegation when he said this: “If the next speaker looks familiar, it’s probably because he’s on the news more often than the lottery or Powerball numbers.”

If you guessed notoriously press-friendly Sen. Charles Schumer (D-N.Y.), you’re correct.

Kudos to Silver for giving us a brand-new Schumer-loves-media line, since the old adage that “the most dangerous place in Washington is between Chuck Schumer and a camera” was getting just a little worn out.

McCain’s Star Search. Throngs of A-list celebrities are expected in Denver throughout the week to support presumptive Democratic presidential nominee Sen. Barack Obama’s (Ill.) bid for the White House. But presumptive Republican nominee Sen. John McCain apparently doesn’t want folks to forget that there are, in fact, real-life celebrities out there who like him, too.

On Monday, reggaeton (the rap-reggae-Latin hybrid) singer Daddy Yankee appeared with McCain in Phoenix to officially endorse the Arizona Republican’s candidacy, calling him “the best guy to lead this nation.” McCain’s campaign immediately sent out an “In Case You Missed It” press release on the endorsement, complete with a video clip of the “Gasolina” singer’s appearance with McCain.

Daddy Yankee joins “The Hills” villainess Heidi Montag and former “Law & Order” actress Angie Harmon in supporting McCain. Impressive as it is, that list just can’t match the star power of Obama, who counts Oprah Winfrey, Ben Affleck and Beyoncé on his list of famous friends.

Consolation Prize: Book Sales? What do you do at a political convention if your candidate, um, doesn’t win the primaries? For Terry McAuliffe, buckraker extraordinaire for Sen. Hillary Rodham Clinton (D-N.Y.), you hawk books. McAuliffe, looking positively chipper, was signing books Monday morning at the downtown convention center — specifically, “What a Party! My Life Among Democrats: Presidents, Candidates, Donors, Activists, Alligators, and Other Wild Animals.”

Not only that, he was scheduled to pull another two-hour shift of autographing Tuesday morning. Best of all, his book’s a steal — a “convention special” of $10 a pop, with a photo with the author gratis. That price was seriously undercutting his booth-mate, Rep. Carolyn Maloney (D-N.Y.), whose “Rumors of Our Progress Have Been Greatly Exaggerated: Why Women’s Lives Aren’t Getting Any Easier — and How We Can Make Real Progress for Ourselves and Our Daughters” was selling at a relatively bloated 30 bucks. Asked if he’s “psyched” for the convention, McAuliffe said, “I am. I love these things.”

Pepsi, Challenged. You’d think if there’s one thing they could get right in Denver’s Pepsi Center, it’s soda. But for a brief while on Monday afternoon, one of the Pepsi machines in the main concourse of the Democrats’ convention venue was on the fritz, spewing forth Mountain Dew instead of Sierra Mist. (Imagine the caffeine wallop in store for the unsuspecting customer!)

A counter worker sprung into action, directing the rest of her crew to switch all orders to the other machine. Then, an order of Sierra Mist came out as flavorless seltzer water. Fortunately, a Pepsi technician sprung into action and quickly fixed the malfunction, earning customers’ gratitude.

Louis Jacobson of CongressNow and Emily Pierce contributed to this report.

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