Forget procrastinating on Facebook or even posting embarrassing party pictures — Capitol Hill staffers may face a bigger peril when it comes to social networking.

[IMGCAP(1)]Top staffers are being warned that a new site created for Members of Congress and their staffs to mix and e-mingle, National Journal’s 3121, might just put them on the wrong side of Senate rules.

An e-mail from a key aide warned that joining the networking site, whose name comes from the Capitol switchboard’s phone extension, might result in a breach of Senate rules.

According to several people familiar with the e-mail, it cautioned that officials hadn’t ruled on whether joining the exclusive group is a no-no.

“It was an informal, heads-up kind of e-mail,— says one Senate staffer.

Senate rules bar staffers from accepting most gifts, and several sources said some staffers worry that membership itself could constitute a banned gift. In addition, the e-mail cited fears that those using the site might threaten “the security and confidentiality of official Senate information.—

The site encourages Hill staffers to “collaborate on projects— for work, according to its marketing materials.

“Based on preliminary reviews, staff had concerns about whether Senate staffers could participate and still be in compliance with the rules,— Senate Rules and Administration Committee Staff Director Jean Bordewich tells HOH.

The Rules Committee, in consultation with the ethics panel and the Office of Legal Counsel, is expected to issue guidance on the matter once it reviews the site.

National Journal Group President Suzanne Clark said in a statement to HOH that the site was developed with the help of Capitol Hill staff. “Beginning last year, we had multiple consultations with senior House and Senate staff to ensure that we complied with all rules,— she said. “We will continue to work with the Hill to ensure that 3121 is a secure, trusted and approved feature of nationaljournal.com.—

An invitation to join the network that National Journal e-mailed to Senate staffers last week boasts that hundreds of Hill staffers have already signed up.

Keeping It Real. Members of Congress might get to wear those fancy pins and have interns fetch them coffee, but underneath all those trappings of power, they’re just regular folks who put their pants on one leg at a time — just like the rest of us. HOH spotted a couple Members on Saturday engaged in nonglamorous pursuits with which even the frowziest of housewives would be familiar.

An HOH spy eyed Sen. Mark Begich carrying several plastic bags while coming out of the Giant grocery store at Rhode Island Avenue on Saturday. HOH hears that the Alaska Democrat and his son, Jacob, were picking up Halloween candy for trick-or-treaters and had stopped by the Giant after a visit to the nearby Home Depot.

The father-son duo actually visited the home improvement warehouse (Jacob’s favorite store!) three times during the weekend to pick up supplies for various projects, a Begich spokesman told HOH.

And that was Rep. Jim McGovern (D-Mass.) standing in line with the masses along with his family at Calvin Coolidge High School to get the H1N1 vaccine for his kiddies. The wait for the shots was almost two hours, our spy says, but there was no VIP access for the Congressman and his family, who cooled their heels just like the other regular peeps.

Playing Politics. When Rep. Bob Sanders announced last week that he’s running to be the next Senator from Pennsylvania, many questioned the feasibility of his campaign. Mostly, people wondered who the heck this “Bob Sanders— person was.

Turns out, Sanders isn’t even real — he’s a fictional character on “Moving Numbers,— a series premiering Wednesday on the Web-based political entertainment network Zolitics.com. And although the e-mail was delivered to drum up publicity for the upcoming series, one of the show’s creators tells HOH that political veterans who watch the show will easily recognize the characters involved in the fictional campaign.

“It’s not based on any one person, but a conglomerate,— said Leslie Gromis Baker, who worked on former President George W. Bush’s 2004 re-election campaign and advised Sen. John McCain (R-Ariz.) during his presidential bid last year. “Everybody will see the different characters and say, ‘Oh, I remember when I worked with so-and-so … People can at some point relate to a campaign they’ve been involved in.—

Several political veterans are working on the series, including GOP media consultant John Brabender and Democratic media consultant Tad Devine. And several notables are expected to make appearances in its 12-episode run, including pollster Frank Luntz and Democratic strategist Robert Shrum.

The show centers on campaign manager Jason Mahoney as he tries to get his boss elected while dealing with some wacky colleagues, which include several types sure to be familiar to Washingtonians: a “manic— consultant, a “depressed pollster— and a “beautiful communications director.— And then there’s the candidate’s wife, who “wants to have a say in everything that’s going on,— Gromis Baker said.

Brotherly Love. The Senator from Minnesota won’t be the only famous Franken in town Friday night.

Sen. Al Franken (D) and his wife, Franni, are scheduled to host a reception honoring his brother, photographer Owen Franken, at the gallery at Vivid Solutions in Anacostia. An exhibition featuring Owen Franken’s eclectic mix of photos is slated to open at the gallery on Friday.

At the reception, Owen Franken will present a slide show discussing his pieces, some of which will be auctioned off to benefit the ARCH Development Corp., which provides assistance to D.C.-based artists. And HOH hears Al Franken also will take part, drawing his famous freehand (but perfectly drawn) map of the United States and auctioning it off for charity.

Overheard on the Hill. “You are invited to a dinner honoring Senator David Vitter … Paid for By David Vitter for U.S. Senate.—

— Excerpt from an invitation for an upcoming fundraiser for the embattled Louisiana Republican. Hey, nobody wants to throw you a party? Just throw one yourself, in honor of … yourself.

“NY-23 Problems But A Dem Ain’t One.—

— E-mail subject line inspired by Jay-Z’s “99 Problems,— sent to reporters Monday by Democratic National Committee spokesman Hari Sevugan. Clearly the rapper maintains a healthy fan base within the Democratic party — or at least at DNC headquarters.

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