Control of Congress is up for grabs. What's the math for Democrats and Republicans?

With one week until the midterm elections, the majorities of both houses of Congress are in play as voters weigh a midterm check on unified control of government in Washington -- President Donald Trump's hold on the White House and Republican majorities in the House and Senate the past two years.
Republicans hold slim majorities in both the House and Senate and are rallying to preserve them with just days until Election Day.
Democrats on the other hand are trying to make inroads into some traditionally red areas in hopes of picking up crucial seats.
Opens ABC News in a new tab