The 32nd annual Rutgers Chabad National Founders dinner drew its usual crowd of philanthropists, Jewish communal and business leaders, and local and state political figures, including Gov. Chris Christie. But it was an unexpected guest who generated the most buzz.

As the 500 attendees were taking their seats at the Dec. 7 event in the ballroom of the Hyatt Regency in New Brunswick, an excited murmur went through the room. Guests reached for their cell phones to snap photos as ex-Beatle Paul McCartney walked in with longtime girlfriend Nancy Shevell.

Shevell’s father, Myron “Mike” Shevell was one of the night’s honorees — along with Christie — in recognition of his $500,000 gift to create a Torah studies program for Rutgers students, who will receive a certificate and stipend after completing 60 semester hours of study.

Shevell is chair of New England Motor Freight and the Shevell Group and vice chair of New Jersey Transit. McCartney has reportedly been dating Nancy Shevell, a vice president of the family-owned business, since 2007.

The dinner raised $3 million toward the $10 million expansion of Chabad House at Rutgers, increasing the size of what is already the world’s largest Chabad facility by 55,000 square feet. The expansion includes the addition of a boys’ dormitory, enlarged dining facilities, and the first Sephardi synagogue at an American public college campus.

The dormitory is being named in honor of Rabbi Gavriel and Rivkah Holtzberg, the Chabad emissaries killed two years ago in the terrorist attack in Mumbai.

Chabad has reached 80 percent of its fund-raising goal for the expansion, said its executive director, Rabbi Yosef Carlebach. The project is expected to be completed in the spring.

Although Sir Paul, dressed in a suit and high-top sneakers, wouldn’t take questions from the press, he graciously autographed dinner programs and shook hands with fans. He politely demurred and smiled when invited onstage with the rest of the Shevell family, but stood and cheered.

McCartney quietly sat at one of the front tables during the evening and applauded during Christie’s remarks.

The governor was followed by Malcolm Hoenlein, executive vice chair of the Conference of Presidents of Major American Jewish Organizations, the keynote speaker. McCartney also listened and offered polite applause as Hoenlein delivered an impassioned speech focusing on the attempted “delegitimization” of Israel and the need to remain vigilant against anti-Semitism.

As he got up to speak, Hoenlein confessed to the crowd, “I’m nervous. You know, I’ve spoken with presidents and prime ministers — but Paul McCartney.”

Christie, well known as a rock fan, stopped in mid-speech as he glanced at McCartney’s table and remarked, “I can’t believe it; Paul McCartney.”

“I think we witnessed a Hanukka miracle,” Carlebach said of the dinner, which fell on the sixth night of the holiday. “Everyone who came thought they were coming to a small dinner, but when they left they didn’t feel that way.”

Asked if he knew in advance that McCartney was coming or if the rock star made any of the handful of significant anonymous gifts that were announced, Carlebach told NJJN, “I cannot confirm or deny anything about Paul.”

Mike Shevell said he made his donation in memory of his son, Jon, who died in 2008 at age 50 and who had been honored by Chabad in 2006.

“My son, Jon, started this and in his honor, I am finishing this,” he said, adding that he wanted to give Jewish students an incentive “to study the Jewish religion and further their Jewish studies.”