Warren began the week by calling for a new Glass-Steagall Act--the New Deal-era banking reform law that was repealed in 1999. On Monday, both her campaign and the state Democratic Party criticized Brown for accepting donations from J.P. Morgan, and Warren's campaign rolled out another attack on Wednesday, arguing that Brown has actively sought to weaken federal Wall Street reforms.
"She has learned that when you are under attack, you have to respond, and respond quickly and hit back," Democratic strategist Mary Anne Marsh of Massachusetts told Yahoo News.
Despite the hullabaloo over Warren's ancestry, Massachusetts voters aren't seeing the issue play out in attack ads.
In a startling move that sets this race apart from many other high-profile Senate contests this election year, Brown and Warren agreed in January to curb all political attack ads from outside groups by donating to their opponent's charity of choice if outside supporters ignored their request to refrain from airing any ads--positive or negative.
In a state that has traditionally leaned Democratic, both Brown and Warren have run ads in recent weeks featuring their connections to President Obama, though Obama actually appeared in the television commercial for Warren. (Brown, who has touted himself as a bipartisan voice in Washington.)
"She's a janitor's daughter who has become one of the country's fiercest advocates for the middle class," Obama says in Warren's ad.