Senate Republicans are gearing up to overturn a rule from the Consumer Financial Protection Bureau that makes it easier for consumers to sue industry giants. They need a simple majority to do so, and a GOP leadership source confirms they will probably vote today. The regulation, issued in July, prohibits banks from slipping binding arbitration clauses into their customers' contracts for credit cards, bank accounts and other products. The financial services industry has made it a top priority to persuade Congress to scrap the rule, which, by a Treasury estimate, could cost firms $500 million in legal defense fees.