Elizabeth Warren has taken Scott Brown's Senate seat in Massachusetts, news outlets are projecting.

This is a major victory for Democrats. Brown, a Republican, is best known for destroying the Democrat's former majority in the Senate when he took the late Ted Kennedy's seat.

And Wall Street knows what Elizabeth Warren is best known for. A former Harvard law professor and bankruptcy expert, she made waves in Washington as an outspoken critic of Wall Street during and after the financial crisis.

She was also considered to head the Consumer Financial Protection Bureau but was passed over in favor of former Ohio Attorney General Richard Cordray.

And if that isn't enough to scare Wall Street, check out this bit from Warren's Democratic National Convention speech:

People feel like the system is rigged against them. And here's the painful part: they're right. The system is rigged. Look around. Oil companies guzzle down billions in subsidies. Billionaires pay lower tax rates than their secretaries. Wall Street CEOs—the same ones who wrecked our economy and destroyed millions of jobs—still strut around Congress, no shame, demanding favors, and acting like we should thank them.

Anyone here have a problem with that? Well I do. I talk to small business owners all across Massachusetts. Not one of them—not one—made big bucks from the risky Wall Street bets that brought down our economy. I talk to nurses and programmers, salespeople and firefighters—people who bust their tails every day. Not one of them—not one—stashes their money in the Cayman Islands to avoid paying their fair share of taxes.

Sleep tight.