Democrats look to have an edge in their bid to flip the House in the final days of the most expensive midterm election ever.

The party will try to take control of the chamber Tuesday as it competes for dozens of Republican-held congressional seats across the country. Democrats need to win a net 23 GOP-held districts in order to flip control of the House, and are favored to reach that target. Still, only minor shifts across the House map could help Republicans cling to a majority.

A record stream of cash has fueled the Democratic Party's push to check President Donald Trump – and the GOP's bid to hang on to control of Congress. Campaigns, parties and outside groups had already spent $4.7 billion by Monday in congressional races, and are projected to shell out more than $5.2 billion by the end of the election cycle, according to the Center for Responsive Politics. It tops a previous record of about $4.2 billion.

Democratic campaigns have largely drubbed GOP candidates in House swing-district fundraising. It has forced the House Republican campaign arm and outside groups to spend heavily in those contests to catch up.