UPDATE 10:30 p.m. EST: ABC News and Fox News project that Republicans will maintain control of the Senate.
Heading into the election, polling data gave Republicans a decided advantage in maintaining control of the U.S. Senate, while Democrats enjoyed a slightly stronger likelihood of taking the House. According to Nate Silver's FiveThirtyEight on the morning of the election, Republicans had a 4 in 5 chance (80.9%) of maintaining control of the Senate and were likely to end up with 52 seats, a net gain of one seat and one more than they need for the 51-seat majority.
Real Clear Politics' average of the key polls Tuesday morning gave Republicans 49 seats that polling data indicates are highly likely to go their way, including two that "lean" heavily in Republicans' favor (North Dakota and Texas), one (Mississippi's special election) that is "likely" to go to the GOP, and 46 that are fully "safe" or not up. RCP gives Democrats a total of 43 seats that are very likely to go their way (five that "lean," two that are "likely," and 37 that are safe or not up).
If RCP's averages of the polls are correct, that means that just eight Senate seats are truly in play: Arizona, Florida, Indiana, Missouri, Montana, Nevada, Tennessee, and West Virginia. Other races that have garnered a lot of attention include North Dakota and Texas. Below is the final polling data for each of these key races and the latest updates on vote counts.
ARIZONA — Too close to call
With 75% reporting, McSally (R) leads Sinema (D) 49.3 - 48.4. (Updated 8:00 a.m. EST)
The contest for the traditionally center-right Arizona seat left empty by retiring Republican Jeff Flake is one of the Democrats' best hopes of picking up a traditionally red seat. Polling data has consistently shown a very tight race between Republican Rep. Martha McSally and Democrat Rep. Kyrsten Sinema. RCP's average of the latest polls gave McSally a razor-thin 1-point advantage, a statistical tie. The final Gravis poll showed McSally up by 1; Emerson gave Sinema a 1-point edge; HarrisX had McSally up by 3; ABC 15/OH Predictive Insights gave the Republican a 1-point edge; and Trafalgar Group gave McSally a 2-point lead.
FLORIDA — Scott (R) declares victory.
With 100% reporting, Scott (R) defeats Nelson (D) 50.2 - 49.8. (Updated 8:00 a.m. EST.)
Incumbent Democrat Sen. Bill Nelson found himself neck-and-neck with Republican Gov. Rick Scott for the Florida seat, though most of the late polls gave Nelson the edge. RCP's final averages of the recent polls gave Nelson a 2.4% lead over Scott. Quinnipiac's final poll showed Nelson up by 7 points; HarrisX found Scott leading by 2; Emerson gave Nelson a 5-point advantage; St. Pete Polls gave the incumbent a 4-point lead; and Trafalgar Group showed Scott with a slim 2-point edge.
INDIANA — NBC & Fox News project Braun (R) winner.
With 93% reporting, Braun (R) leads Donnelly (D) 52.9 - 43. (Updated 8:00 a.m. EST.)
Incumbent Democrat Sen. Joe Donnelly is one of the senators that appears to have been hurt by his vote against now-Supreme Court Justice Brett Kavanaugh. Real Clear Politics' final average gave him a slim 1.3% advantage over Republican Mike Braun. The final poll by CBS News/YouGov found Braun up by 3 points; NBC News/Marist found Donnelly leading by 2 points; Fox News found Donnelly ahead by 7 points; and the most recent poll, by HarrisX, found Braun with a razor-thin 1-point edge.
MISSOURI — Fox News projects Hawley (R) winner.
With 99% reporting, Hawley (R) leads McCaskill (D) by 51.5 - 45.5. (Updated 8:00 a.m. EST.)
After voting against Kavanaugh, incumbent Sen. Claire McCaskill was on the wrong side of several of the polls in the contest in Missouri against Republican Attorney General Josh Hawley. RCP's final average showed Hawley with a negligible 0.6% edge. Three of the six most recent polls found the two tied. An NBC News/Marist poll found McCaskill ahead by 3 points; Trafalgar Group found Hawley up by 4 points; and Emerson found the Republican leading by 3 points.
MONTANA — Too close to call
With 95% reporting, Rosendale (R) leads Tester (D) 48.8 - 48.3. (Updated 8:00 a.m. EST)
Incumbent Democrat Sen. Jon Tester's once sizable lead over Republican challenger Matt Rosendale diminished somewhat over the past few weeks. Going into election day, he lead by an average of 3.3 points. Gravis's final poll gave Tester a 3-point lead; HarrisX gave him a 6-point lead; and Trafalgar Group gave him just a 1-point edge over Rosendale.
NEVADA - NBC & Fox News project Rosen (D) winner.
With 94% reporting, Rosen (D) leads Heller (R) 49.7 - 46. (Updated 8:00 a.m. EST)
Incumbent Republican Sen. Dean Heller (R-NV) headed into election day tied with challenger Democrat Jacky Rosen in the polls. Trafalgar Group gave Heller a 3-point lead; HarrisX showed Heller leading by just 1-point; and Emerson gave Rosen a 4-point advantage.
NORTH DAKOTA — NBC & Fox News project Cramer (R) winner.
With 99% reporting, Cramer (R) leads Heitkamp (D) 55.4 - 44.6. (Updated 8:00 a.m. EST.)
Incumbent Democrat Sen. Heidi Heitkamp's polling numbers tanked after her vote against Kavanaugh. RCP's final average was a commanding 9-point lead for Republican challenger Kevin Cramer. Both Trafalgar Group and Fox News' final polls gave Cramer that sizable advantage.
TENNESSEE — NBC & Fox News project Blackburn (R) winner.
With 99% reporting, Blackburn (R) leads Bredesen (D) by 54.7 - 43.9. (Updated 8:00 a.m. EST.)
The race for the open seat between Republican Rep. Marsha Blackburn and Democrat Phil Bredesen leaned towards Blackburn for the last few weeks. RCP's final average put her ahead by 5.2 points. Recent polls by CNN, Fox News, and Emerson gave her leads of 4, 9, and 8 points, respectively.
TEXAS — NBC & Fox News project Cruz (R) winner.
With 99% reporting, Cruz (R) leads O'Rourke (D) by 50.9 - 48.3. (Updated 8:00 a.m. EST.)
The contest between incumbent Republican Sen. Ted Cruz and challenger Democrat Beto O'Rourke was tight for several weeks, but moved in Cruz's direction over the last month. RCP gave Cruz a 6.8% lead by average. The final polls by Quinnipiac, CBS 11/Dixie Strategies, Emerson, and Trafalgar Group showed Cruz ahead by 5, 10, 3 and 9 points, respectively.
WEST VIRGINIA — Fox News projects Manchin (D) winner.
With 100% reporting, Manchin (D) leads Morissey (R) 49.5 - 46.3. (Updated 8:00 a.m. EST.)
Though it seemed highly unlikely that incumbent Democrat Joe Manchin would lose his seat to challenger Patrick Morissey, recent polls showed the race tightening. On election morning, RCP gave Manchin a 5-point lead by average, with recent polls by MetroNews and Emerson both showing him ahead by that same margin. Manchin was the only Democrat to break ranks and vote for the confirmation of Kavanaugh.