Americans vote Tuesday in elections that will determine the environment for the rest of Trump's first term

Democrats aim to seize control of both houses of Congress from Republicans

Polls suggest they will likely take control of the House but fall short in the Senate

All 435 House seats are up for grabs along with 35 of the 100 Senate seats and 36 state governorships

A Democrat-led House would launch investigations, issue subpoenas and talk about impeaching Trump

If they control the Senate, the president will lose the ability to easily confirm judges and cabinet members

New ad spending records were set, with more than $3.2 billion in TV and radio ads and $900 million online

36 million Americans had already voted prior to Election Day in 37 states and  D.C. where it's allowed