Senator Elizabeth Warren is calling out regulators after little-known hedge fund Archegos Capital Management was able to borrow so much money that its implosion last week sent shockwaves across Wall Street. "Regulators need to rely on more than luck to fend off risks to the financial system," Warren, a Democrat from Massachusetts, said in a statement to CNN Business. "We need transparency and strong oversight to ensure that the next hedge fund blowup doesn't take the economy down with it."