Naomi Pitcairn of Oakland is detained on Third Street after protesting and leaving a fundraiser at the St. Regis in San Francisco on Thursday. (Lea Suzuki/ The Chronicle)

(Updated with new details, 4:45 p.m.)

Now, this is putting money where your mouth is:

A group of protesters apparently paid tens of thousands of dollars to attend Thursday’s breakfast fundraiser for President Obama and the DNC — then stood up and delivered a song about the treatment of Bradley Manning, the imprisoned army private who gave classified documents to Wikileaks.

Obama was delivering remarks to 150 donors at the St. Regis in San Francisco when an unidentified woman in a white suit stood up and said, “Mr. President, we wrote you a song.”

According to the White House pool report, Obama tried to convince the woman to wait until the end of his speech, but she and a half-dozen others at her table began singing, “Dear Mr. President, we honor you today sir. . .

At first, the president didn’t realize it was a protest, and looked over to Nancy Pelosi to see if she was in on the surprise. Pelosi clearly was not, and the women continued (according to lyrics handed out later to reporters):

It takes a lot of Benjamins to run a campaign

I paid my dues, where’s our change?

We’ll vote for you in 2012, yes that’s true

Look at the Republicans — what else can we do

Even though we don’t know if we’ll retain our liberties

In what you seem content to call a free society

Yes it’s true that Terry Jones is legally free

To burn a people’s holy book in shameful effigy

But at another location in this country

Alone in a 6x12 cell sits Bradley

23 hours a day is night

The 5th and 8th Amendments say this kind of thing ain’t right

We paid our dues, where’s our change?

They held up signs reading, “Free Bradley Manning,” and the ringleader stripped off her white jacket to show a black T-shirt with the same message. At that point, the Secret Service escorted her out. Others at the table walked out, but some stayed until the end of Obama’s speech and applauded at the end. (Hey, why not stay? One of the activists told the San Francisco Chronicle she shelled out $76K to get her group in.)

“That was a nice song,” said Obama dryly. “Now where was I?” Later, press secretary Jay Carney said the president thought it was “funny” and told him, “You don’t get that every day.”

Taking note back in D.C.: Former Mayor Sharon Pratt and her predecessor Walter Washington’s widow Mary. The two women went to the White House Thursday in an attempt to hand-deliver a letter — co-signed by Vince Gray, Tony Williams and Marion Barry — asking Obama to put the city’s “Taxation without Representation” plates on his official vehicles. (Clinton did, Bush removed them, and Obama has thus far rebuffed efforts to get involved.) But Secret Service told them they wouldn’t take a letter by hand — mail only. Pratt told us they’re hoping to get it to him in person, “at an event or wherever — we’re determined it’s going to get his attention.” How about at a fancy fundraiser? “That’s an option we need to consider. We need to exhaust all options, to let them know it matters to us.”

A video of the protest, courtesy of the San Francisco Chronicle.