BOSTON – Elizabeth Warren opened for President Obama at his Boston fund-raiser on Monday, ripping into his rival, Mitt Romney, the former governor of Massachusetts, using themes from her own campaign.

Ms. Warren, the Democratic candidate for Senate in a fierce race against the Republican incumbent Senator Scott Brown, received a thunderous welcome from the fund-raiser’s 1,800 attendees at Boston’s Symphony Hall.

“This election will be about whose side you stand on,” said Ms. Warren, repeating a line that she frequently uses on the campaign trail. “Over the past few years, I’ve seen whose side the president stands on.”

Drawing on her work as a special aide in the Obama administration, where she created the Consumer Financial Protection Bureau, Ms. Warren praised Mr. Obama’s work on financial reform.

“Big banks and Republicans fought tooth and nail against us, they vowed this agency would never become law. And when the money poured in, when the pressure mounted against us and when we were on the ropes, President Obama stood firm,” Ms. Warren said. “He planted his feet, he squared his shoulders, and he said, We will stop the cheating, we will stop the tricks and traps.”



Ms. Warren used the theme of financial regulation a second time to deride Mr. Romney.

“They want to repeal all of the financial reforms,” Ms. Warren said of Mr. Romney and Congressional Republicans.

“Mitt Romney tells us in his own words, ‘I think corporations are people.’ No, Mitt, corporations are not people. People have hearts, they have kids, they get jobs,” Ms. Warren said. “Learn the difference.”

“And Mitt, learn this,” she continued, delivering one of the night’s strongest lines, “We don’t run this country for corporations, we run it for people.”

Ms. Warren did not mention Mr. Brown, her Senate rival, during her speech, but her campaign has worked to depict him as an ally to Mr. Romney. “A vote for Scott Brown is a vote for President Mitt Romney, the Republican Party, Wall Street, and the big corporations,” read a campaign e-mail sent in April.

Mr. Obama briefly thanked Ms. Warren at the beginning of his 40-minute speech. “Nobody fought harder for Wall Street reform — reform that is now law and protecting consumers around the country — than Elizabeth,” Mr. Obama said.

William Terry, a doctor from Newton, Mass., said he found the two to be a convincing pair – although he said it reminded him of how Ms. Warren was unable to get Congressional approval to run the Consumer Financial Protection Bureau.

“I believe what he said — that she’s been a fighter for the kinds of things they both believe in,” said Dr. Terry, who said he was excited about Ms. Warren’s Senate run, but added, “I think it would have been better if she’d been able to be the leader of the band.”