Democrats moved one seat closer to taking back control of the Senate Tuesday night, as Democrat John Hickenlooper defeated incumbent Republican Sen. Cory Gardner in Colorado, the Associated Press reports.

Thanks to Hickenlooper’s victory, Democrats now need a net gain of two seats to regain control of the Senate if former Vice President Joe Biden wins the presidential election — three if President Donald Trump is reelected. They’ll also have to overcome the likely loss of Alabama Sen. Doug Jones, who doesn’t have the benefit of running against an accused child molester this time around.

Democrats also didn’t get any help in South Carolina, where incumbent Republican Sen. Lindsey Graham prevailed against challenger Jaime Harrison, who lost despite raising over $100 million.

Here are the 11 Senate seats that appeared most up for grabs heading into election night:


Alabama

Alabama Senate race: Incumbent Doug Jones (Democrat) vs. Tommy Tuberville (Republican)
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Alabama Senate race: Incumbent Doug Jones (Democrat) vs. Tommy Tuberville (Republican)
  • Incumbent: Doug Jones, Democrat
  • Challenger: Tommy Tuberville, Republican
  • Cook Political Report rating: Lean Republican
  • 2020 Results: Tuberville leads Jones by nearly 17 percentage points (42% of votes reported)

Sen. Doug Jones appears on course to lose his seat to challenger Tommy Tuberville, a former college football coach who defeated Jeff Sessions in the Republican primary. A recent Morning Consult poll ahead of the election had Tuberville up by 12 points, which isn’t surprising considering the state’s last Democratic Senator — Richard Shelby — switched parties to become a Republican during President Bill Clinton’s first term.


Alaska

Alaska Senate race: Incumbent Dan Sullivan (Republican) vs. AlGross (Democrat)
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Alaska Senate race: Incumbent Dan Sullivan (Republican) vs. AlGross (Democrat)
  • Incumbent: Dan Sullivan, Republican
  • Challenger: Al Gross, Democrat
  • Cook Political Report rating: Lean Republican
  • Polls close: 1 a.m. Eastern

Up in the Last Frontier, a surprisingly close Senate race has challenger Al Gross — an orthopedic surgeon and former commercial fisherman with no previous experience in public office — eying an upset over incumbent Sen. Dan Sullivan. Both have crisscrossed the massive state over the past few weeks, according to the Anchorage Daily News, with a recent Gravis Marketing polls showing Sullivan up by just three points.


Arizona

Arizona Senate race: Incumbent Martha McSally (Republican) vs. Mark Kelly (Democrat)
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Arizona Senate race: Incumbent Martha McSally (Republican) vs. Mark Kelly (Democrat)
  • Incumbent: Martha McSally, Republican
  • Challenger: Mark Kelly, Democrat
  • Cook Political Report rating: Lean Democratic
  • 2020 Results: No results reported

Former astronaut Mark Kelly has a strong lead over incumbent Sen. Martha McSally heading into Tuesday’s election, according to recent polls. The defining moment of the race might have been earlier this month, when McSally was caught flat-footed when asked during a debate if she was proud of her support for Trump. The result was a tense campaign stop earlier this week, where Trump rushed her on and off the stage during a rally.


Colorado

Colorado Senate race: Incumbent Cory Gardner (Republican) vs. John Hickenlooper (Democrat)
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Colorado Senate race: Incumbent Cory Gardner (Republican) vs. John Hickenlooper (Democrat)
  • Incumbent: Cory Gardner, Republican
  • Challenger: John Hickenlooper, Democrat
  • Cook Political Report rating: Lean Democratic
  • 2020 Result: Hickenlooper win

Despite a lackluster showing during the 2020 Democratic presidential primary (he was mistaken for a reporter ahead of a debate), John Hickenlooper looks to be on his way to defeating incumbent Sen. Cory Gardner and flipping the seat for the Democrats. Hickenlooper, a Main Line native and Colorado’s former governor, has a strong lead over Gardner in recent polls of the race.


Georgia

Georgia Senate race: Incumbent David Perdue (Republican) vs. Jon Ossoff (Democrat)
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Georgia Senate race: Incumbent David Perdue (Republican) vs. Jon Ossoff (Democrat)
  • Incumbent: David Perdue, Republican
  • Challenger: Jon Ossoff, Democrat
  • Cook Political Report rating: Toss up

Sen. David Perdue, the former Dollar General CEO turned senator, finds himself in a surprisingly tight race against 33-year-old challenger Jon Ossoff. Perdue, who is among Trump’s favorite golf partners on Capitol Hill, drew widespread criticism for intentionally mispronouncing Kamala Harris' name at one of the president’s rallies earlier this month (they both serve together on the Senate Budget Committee).


Georgia

Georgia Senate race: Incumbent Kelly Loeffler (Republican) vs. Raphael Warnock (Democrat)
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Georgia Senate race: Incumbent Kelly Loeffler (Republican) vs. Raphael Warnock (Democrat)
  • Incumbent: Kelly Loeffler, Republican
  • Challenger: Raphael Warnock, Democrat
  • Cook Political Report rating: Toss Up
  • Note: If no candidate receives 50% of the vote, the race will have a run-off

A second Georgia senate seat is up for grabs Tuesday night, thanks to a special election to replace retired Sen. Johnny Isakson. Sen. Kelly Loeffler is the incumbent, but has been pushed to the far right thanks to a challenge from former Georgia Rep. Doug Collins. That has allowed Raphael Warnock, a prominent Black preacher who is the pastor of Atlanta’s storied Ebenezer Baptist Church, the opportunity to win the seat away from Republicans. Polls show Warnock leading the crowded field heading into Election Day, but could fail to garner enough votes to prevent a runoff thanks to a challenge from Democrat Matt Lieberman, the son of former Connecticut Sen. Joseph Lieberman.


Iowa

Iowa Senate race: Incumbent Joni Ernst (Republican) vs. Theresa Greenfield (Democrat)
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Iowa Senate race: Incumbent Joni Ernst (Republican) vs. Theresa Greenfield (Democrat)
  • Incumbent: Joni Ernst, Republican
  • Challenger: Theresa Greenfield, Democrat
  • Cook Political Report rating: Toss up

If Sen. Joni Ernst ends up losing her reelection bid, it might just be because she didn’t know the price of soybeans. Ernst, the first woman to represent Iowa in Congress, answered incorrectly during a debate earlier this month the current price of soybeans was “about $5.50.” (it was $10.05). It doesn’t help matters that her challenger, Theresa Greenfield, nailed her answer about the price of corn. That this senate race is tight heading into Election Day is a major surprise, considering Trump won Iowa by nearly 10 percentage points in 2016.


Maine

Maine Senate race: Incumbent Susan Collins (Republican) vs. Sara Gideon (Democrat)
AP Photos
Maine Senate race: Incumbent Susan Collins (Republican) vs. Sara Gideon (Democrat)
  • Incumbent: Susan Collins, Republican
  • Challenger: Sara Gideon, Democrat
  • Cook Political Report rating: Toss up

Democrats have been eying this race since Sen. Susan Collins voted to confirm Supreme Court Justice Brett Kavanaugh in 2018. Collins, a moderate Republican vying for her fifth term, finds herself down in the polls to Sara Gideon, the Speaker of the Maine House. Collins chances also aren’t helped by the state’s ranked-choice system, which uses a voters second choice if no one reaches 50% when the first-choice votes are counted (progressive independent candidate Lisa Savage has asked her voters to list Gideon as their second choice).


Montana

Montana Senate race: Incumbent Steve Daines (Republican) vs. Steve Bullock (Democrat)
AP Photos
Montana Senate race: Incumbent Steve Daines (Republican) vs. Steve Bullock (Democrat)
  • Incumbent: Steve Daines, Republican
  • Challenger: Steve Bullock, Democrat
  • Cook Political Report rating: Toss up

Steve Bullock, a two-term Montana governor who didn’t exactly set the world on fire during the Democratic presidential primary, hopes to have better luck tonight against incumbent Sen. Steve Daines. Polls show the race is a toss-up, and Daines — an outspoken Trump supporter — might have benefited from a visit by the president, who won Montana by 20 points in 2016. Instead, Daines had to settle for an 8-1/2 minute “tele-rally” with Trump earlier this month.


North Carolina

North Carolina Senate race: Incumbent Thom Tillis (Republican) vs.Cal Cunningham (Democrat)
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North Carolina Senate race: Incumbent Thom Tillis (Republican) vs.Cal Cunningham (Democrat)
  • Incumbent: Thom Tillis, Republican
  • Challenger: Cal Cunningham, Democrat
  • Cook Political Report rating: Toss up

Cal Cunningham has maintained his slight polling edge over incumbent Sen. Thom Tillis despite a scandal involving romantic texts with a woman who isn’t his wife. Tillis, who was among the Republicans who contracted COVID-19 after attending an event at the White House earlier this month, has been criticized for standing by Trump’s response to the pandemic. It has also been the most expensive U.S. Senate race in the history of the country, surpassing $285 million, according to the Center for Responsive Politics.


South Carolina

South Carolina Senate race: Incumbent Lindsey Graham (Republican) vs. Jamie Harrison (Democrat)
AP Photos
South Carolina Senate race: Incumbent Lindsey Graham (Republican) vs. Jamie Harrison (Democrat)
  • Incumbent: Lindsey Graham, Republican
  • Challenger: Jaime Harrison, Democrat
  • Cook Political Report rating: Toss up

Sen. Lindsey Graham is in the fight of his political life thanks to a surprisingly tight race against challenger Jaime Harrison. Graham, a one-time Trump critic who has become one of the president’s most outspoken supporters, has been forced to appear multiple times on Fox News to ask for campaign cash thanks to the more than $100 million raised by Harrison, a former lobbyist and state party chair. Polls show a tight race, though FiveThirtyEight gives Graham a 79% chance of winning Tuesday night.


Other Senate races to watch

  • Kansas: Republican Roger Marshall vs. Democrat Barbara Bollier (open seat)
  • Michigan: Democrat Sen. Gary Peters (incumbent) vs. Republican John James
  • Texas: Republican Sen. John Cornyn (incumbent) vs. Democrat MJ Hegar

The Associated Press contributed to this article.