The GOP will start whittling away at Obama's regulatory legacy on Jan. 30 and cut away for two weeks, Republican leader Kevin McCarthy said. Reuters has the details of what they're going after first:

• Workplace pay rules that track worker gender, race and ethnicity
• Environmental rules on the impact of coal mining, and curbs of methane leaks

Then they'll take on more regulations on labor, energy and the environment, banking and finance, transportation, education, and media ownership.

The mechanism: Under the Congressional Review Act, which lets Congress overturn recently implemented rules, these steps only need simple majority so there is little Democrats in either the House or Senate can do to do stop it.