Henry Rodgers of the Daily Caller offers a status report on hotly contested national congressional battles in the midterm election.

Both Democrats and Republicans are gearing up for some extremely tight races across the country.

According to a majority of polling, Republicans are expected to lose control of the House but keep control in the Senate after the Nov. 6 midterm elections. However, there is growing speculation that Republicans could be more successful than polls suggest.

In the Senate, there are six seats that are currently listed as “toss up” elections, four of which belong to current Democratic senators, according to Real Clear Politics. Republicans need to maintain 51 seats in the Senate in order to keep majority.

Five of the candidates in those “toss up” Senate races are incumbents, including Democrats Jon Tester of Montana, Bill Nelson of Florida, Joe Donnelly of Indiana, Claire McCaskill of Missouri, and Nevada Republican Sen. Dean Heller. The Senate race in Arizona is also listed as a toss-up, as Republican Rep. Martha McSally is running against Democratic Rep. Kyrsten Sinema for GOP Sen. Jeff Flake’s seat, who announced in October 2017 that he would not seek re-election.

Democrats have been predicting a “blue wave” for the midterm elections, hinting that they will win back a majority in the House and pick up a large number of seats in local state races and gubernatorial races across the country.

In the House, there are 32 seats that are listed as “toss up” elections. Democrats must pick up at least 24 seats in order to get to the 218 seats needed for majority.

While Democrats are expected to win control of the House, Republicans could pick up a few Senate seats from toss up races.