The massive Equifax Inc. data breach has triggered demands on Capitol Hill for stiffer rules and new requirements for what financial companies must do to fend off cyberattacks.

Yet tougher oversight would all but certainly require support from the Trump administration and buy-in from congressional Republicans — both of whom want to reduce financial regulation not stiffen it. Democrats so far have led the calls for more rules in the wake of Equifax's disclosure that 143 million Americans' personal information was stolen.

Tighter constraints would pose a particularly difficult choice for GOP lawmakers because it would most likely mean further empowering the Consumer Financial Protection Bureau, a controversial agency created after the 2008 financial crisis that many Republicans have been trying to weaken or put out of business almost from its first day of existence. No other federal regulator supervises Equifax or has officials inside the firm conducting on-site exams.