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With six and a half weeks until Election Day, Democrats have managed to hang on to a path to take back the Senate majority for the first time since 2014. If they win the majority in November, it could end Republicans' chances to confirm Judge Brett M. Kavanaugh for the Supreme Court, whose nomination is currently roiled by a sexual assault allegation he denies.

But Democrats will have to have a near-perfect run of the top 10 races below to do it.

Some crucial details are trending Democrats' way: They have a popular former governor who is making an open seat in Tennessee surprisingly competitive, while what seemed to be potentially competitive races to unseat Democrats in Michigan, Ohio and Pennsylvania are not really on the radar, anymore. And it is not in our top 10, but liberal star Rep. Beto O’Rourke (D) has forced all eyes on Texas as he makes a buzzy — if still a long-shot — effort to unseat Sen. Ted Cruz (R).

Here is an updated look at the top 10 most competitive Senate seats of the 2018 election cycle. We have ranked them from least likely to flip parties (10) to most likely (1) and will rank them again before Election Day.

10. Tennessee (open seat), no ranking change from The Fix’s last top 10 list: National Democrats continue to be impressed with how competitive former Democratic Tennessee governor Phil Bredesen is making the race to replace retiring Sen. Bob Corker (R). Bredesen has been airing ads since March portraying himself a common-sense, moderate governor. (It helps that he has more than $100 million of his own money to spend.) Republicans also like their nominee, Rep. Marsha Blackburn. This is a tight race, which is good news for Democrats because it slightly increases their chance to take back the majority.


Former Tennessee governor Phill Bredesen campaigns in June. (Jonathan Mattise/AP)

9. Wisconsin (D), no ranking change: Sen. Tammy Baldwin is trying to remain one of Wisconsin’s only statewide-elected Democrats. So far she is hanging on against state Sen. Leah Vukmir. Two polls since the August primary finalized the race show Baldwin up by 8 and 11 points. But it is not over yet: Conservative outside groups are pouring in millions to knock off Baldwin, and Republicans are hoping a competitive governor’s race to re-elect Gov. Scott Walker (R) will rally voters for Vukmir.

8. West Virginia (D), previous ranking 7: Of all the red-state Senate Democrats, Sen. Joe Manchin III probably has the strongest brand back home. And he will need it, given Trump won West Virginia by more than 40 points. But we keep marking this race less competitive (it started out the election season in the top five), because Manchin keeps proving hard for his opponents to knock off, especially when some Republicans believe their nominee, West Virginia Attorney General Patrick Morrisey, has proved a lackluster candidate. One Republican described Manchin as “the mayor of West Virginia.”


Sen. Joe Manchin (D-W.Va.) speaks with reporters in the Senate in January. (Andrew Harnik/AP)

7. Montana (D), previous ranking 8: Sen. Jon Tester’s (D) reelection race moves up a spot in competitiveness mostly because West Virginia moves back. Unluckily for Tester, he is the Democrat Trump likes to attack the most in a state Trump won by 20 points. The president has already been to Montana to campaign for Tester’s opponent, Matt Rosendale — who has decked out his social media accounts of pictures of him on stage with Trump. But Montana voters march to the beat of their own drum. They reelected a Democratic governor, Steve Bullock, the same year they voted for Trump by more than 20 points. A recent CBS poll shows this race within the margin of error.

6. Florida (D), no ranking change: The only current statewide elected Democrat in Florida, Sen. Bill Nelson, is trying to hang on as tens of millions of dollars are being spent against him by and for his wealthy opponent, Gov. Rick Scott (R). Despite that, the race has been tied for months, and Democrats are calculating that high turnout of the kind seen in the primary and earlier special elections will put Nelson over the edge. Republicans remain confident in Scott — and his millions.

5. Arizona (open), no ranking change: To take back the Senate majority, Democrats almost certainly have to win retiring Sen. Jeff Flake’s (R) seat. Their hopes are pinned on Rep. Kyrsten Sinema (D), a moderate congresswoman trying to be the first statewide Democrat elected in Arizona since the George W. Bush years. Her opponent is Rep. Martha McSally (R), a former fighter pilot who survived a chaotic primary and is cozying up to Trump to turn out Republicans' base. Most polls show this race within the margin of error, which is a good sign for Democrats. This will be a tug-and-pull between enthusiasm on the left and the conservative underpinnings of the state.


Rep. Kyrsten Sinema (D-Ariz.) speaks with volunteers in Phoenix in August. (Matt York/AP)

4. Indiana (D), previous ranking 2: Making Sen. Joe Donnelly’s (D) reelection less competitive may be the biggest change on our list. Once seen as the most vulnerable red-state senator, Donnelly is holding on against a businessman who beat out two congressmen for the Republican nomination, Mike Braun. But Braun may be too much of a novice for such a competitive race. The Associated Press reports he has yet to purchase ads for October, while Donnelly is outspending him on radio and TV by almost double for months.


Mike Braun speaks with employees of Green Leaf in Fontanet, Ind., in September. (Austen Leake/The Tribune-Star/AP)

3. Missouri (D), no ranking change: Claire McCaskill remains one of the most endangered Senate Democrats this November. She is a talented politician who has won tough races before, but this is as tough a battle as she will have faced. After initial criticism from some in his party, her GOP opponent, Attorney General Josh Hawley, seems to have righted his ship. This race is neck-and-neck. Slightly more Missouri voters disapprove of Trump (46 percent) than approve (44 percent) in a new NBC News/Marist poll. That might explain why McCaskill said this week she will oppose Kavanaugh for the Supreme Court.

2. North Dakota (D), previous ranking 4: Sen. Heidi Heitkamp (D) is now Senate Democrats' most vulnerable incumbent. While she is generally a well-liked politician, North Dakota may be too Republican a state for her to survive. There, Republicans have their top recruit, Rep. Kevin Cramer (R), who knows how to run a statewide campaign since North Dakota only has one congressional district. Private Republican polls show Cramer leading in the high single digits.


Democratic Sen. Heidi Heitkamp and her Republican challenger Kevin Cramer. (AP)

1. Nevada (R), no ranking change: It is a Republican, Sen. Dean Heller, who remains The Fix’s most vulnerable senator. While Heller is running for reelection in a state Hillary Clinton won by a couple of points (as compared with Heitkamp trying to hang on in a state Trump won by 35 points), the national Democratic energy could be most concentrated in Nevada. Rep. Jacky Rosen (D), Heller’s opponent, has a mix of unions, Latino and other minority voters and youths to stand upon. Heller has tied his reelection to Trump, who was in Las Vegas campaigning for him on Thursday night.

Correction: This post originally misspelled West Virginia Attorney General Patrick Morrisey’s name.