It was a drubbing on a scale that neither side saw coming: Democrats pummeled Republicans across the battleground map and into some of the most MAGA-friendly terrain in the country.Why it matters: The results were an emphatic rejection of Donald Trump's second term in office — and set the stage for two years of corruption investigations and legislative frustration for the lame-duck president.Here's a rundown of what you need to know about last night's historic GOP beatdown.