Elizabeth Warren, clad in cardigans and pearls, has become Wall Street's public enemy No. 1, but it's that very vitriol that could earn her a post heading the government's new consumer watchdog agency. ... Warren, a Harvard law professor and outspoken consumer rights advocate, is currently a top monitor of the government's $700bn bailout of the financial system. Now she is one of the main contenders to head the Consumer Financial Protection Bureau, an agency to regulate financial products ranging from credit cards to mortgages.