Five years after President Barack Obama slammed Wall Street "fat cat" bankers, some of the nation's biggest banks this week successfully lobbied Congress to roll back a hotly debated provision in the 2010 Dodd-Frank financial reform law.

The question is whether bankers can keep up their winning streak.

The early view is that Wall Street, insurers, and companies that deal in complex financial instruments will secure targeted victories in 2015, especially with Republicans in control of the Senate.