Maine: Susan Collins has been a United States Senator from Maine since 1997. “I want to continue the independent, moderate, and thoughtful tradition of Bill Cohen”, Senator Collins once said. Despite being a member of the Republican Party, she has always seen to have represented a moderate side of the party. Up until Trump came to office. Her opponent, Sara Gideon, serves as the Speaker of the Maine House of Representatives. She is the democratic nominee for U.S. Senate from Maine for the upcoming election against Susan Collins.In the polls, Gideon is in a lead with 49% of a Suffolk University poll, whereas, the incumbent is down 7 points from that. Now, Maine is a state where there are more independents than the republicans. Usually, independents side with democrats, which would lean the election towards Gideon. South Carolina:The incumbent Republican Senator from South Carolina Lindsey Graham is up for re-election. He has served on the seat since 2003. Back in 2016, he was one of the Candidate Trump`s fiercest critics. Over the years after President Trump`s rise to power, Graham has started to side with him, even over his past comments. His opponent, Jamie Harrison, was a chair of the South Carolina Democratic Party from 2013 to 2017. Now, he is the Democratic Nominee for Senate from S.C. His race is one of the most significant toss-ups this year.In the polls, Jamie Harrison is even with Lindsey Graham at 48%, according to a Quinnipiac University poll. In the same state, Trump is leading the polls with 6 points. Arizona:After Senator John McCain`s death two years ago, Martha McSally was appointed as the junior United States Senator for Arizona. The seat is up for re-election.In the polls, the democratic nominee Mark Kelly is leading with 6 points, according to a Change Research poll. This is a special election. This would swear in the Senator in Late November instead of January. Therefore, it would clearly influence the Supreme Court confirmation process.Michigan:In Michigan, the polls are showing an ugly picture for the President`s likability. AKiaer Research Poll shows Biden leading Trump by 15 points. Most polls have mostly started to show his double-digit leads in Michigan. In 2016, Clinton led the polls by 5 points over Trump. Moreover, for the U.S. Senate race this year, Senator Peters has a double-digit lead over the republican candidate John James.North Carolina:Thom Tillis, the incumbent U.S. Senator from North Carolina is in a tough position. He has been a U.S. Senator since he was elected in the 2014 mid-terms, defeating incumbent Kay Hagan (D-NC).Chris Cunningham, his democratic challenger is starting to gain lead in a state starting to tilt blue for this election season. Even the gubernatorial polls show the current democratic Governor of North Carolina is already ahead in many polling numbers brought by both Meredith College and Harper Polling.California:If Joe Biden does get elected into the White House, there is an opportunity for many to be appointed to Senator Kamala Harris` (D-CA) seat.Alabama:Incumbent Democratic Senator Doug Jones was elected in a special election in 2017.This year, he is up against Tommy Tuberville, Former Auburn University football head coach and the Republican nominee who seems to be gaining real support from voters which looking as a likely toss-up seat.Colorado:Colorado Senator Cory Gardner was elected in 2014 after serving four years in the House of Representatives. His seat is likely to go to Former Colorado governor John Hickenlooper.In the polls, Hickenlooper is up by 7 points at 49%, according to one Morning Consult poll.Overall, these Senate seats are essential if either side wants to reach an agreement on Stimulus checks for millions of Americans and the upcoming Presidential Election.