GOP's grip on the Senate tightens even as Democrats threaten to take the House

Key Points
  • Only 3½ weeks before the midterms, Democrats' chances of taking the Senate and House are diverging.
  • Nonpartisan forecasters consider Republicans strong favorites to keep Senate control, while Democrats are in a good position to take the House.
Senate Minority Leader Charles Schumer, D-N.Y., right, and Senate Majority Leader Mitch McConnell, R-Ky.
Tom Williams | CQ Roll Call | Getty Images

With less than a month to go until November's midterm elections, the battles for both chambers of Congress are diverging.

Republicans' hold on their Senate majority appears to have tightened in the wake of Supreme Court Justice Brett Kavanaugh's confirmation, but Democrats are favorites to seize control of the House as more key GOP-held seats tilt away from Republicans, according to top election forecasters.

Recent developments have only strengthened this year's prevailing narrative: that Democrats will likely struggle to navigate the Senate even as party enthusiasm helps them unseat vulnerable House Republicans across the country. Split partisan control of Congress appears to be the most likely scenario when the new session starts in January.

Democrats need to flip 23 GOP-held districts to take control of the House. If Republicans can stop Democrats from taking two Senate seats — a manageable task as Democrats and independents who caucus with them defend 26 seats — they will hold their Senate majority.

Of course, much can change in 3½ weeks, but here is how top forecasters viewed the midterm battlefield as of Thursday afternoon:

The Senate

Three factors will determine if Democrats will take back Congress
  • Analysts broadly consider 10 Senate races — six held by Democrats and four by Republicans — the most competitive this year. Those contests are in Arizona, Florida, Indiana, Missouri, Montana, Nevada, North Dakota, Tennessee, Texas and West Virginia. President Donald Trump won all but one of those states in 2016, and easily carried most of them.
  • Republicans have about an 81 percent chance of keeping a Senate majority, according to data site FiveThirtyEight. That figure rose from 78 percent on Oct. 4. The site forecasts an average gain of about a half a Senate seat for the GOP.
  • The nonpartisan Cook Political Report rates nine of those 10 key races as toss-ups, with only Democratic-held West Virginia listed as "lean" Democratic.
  • Sabato's Crystal Ball, another nonpartisan forecaster, considers five of those races toss-ups. It rates GOP-held Tennessee and Texas, as well as Democratic-held North Dakota, as "leans" Republican. West Virginia also falls under "leans" Democratic.

Republicans saw positive signs in a few races in recent days. Sabato's Crystal Ball moved the North Dakota race to leans Republican on Thursday as polls increasingly show Democratic Sen. Heidi Heitkamp facing a deficit against GOP Rep. Kevin Cramer. The senator is considered the member of her party most likely to lose this year.

Separate Quinnipiac University and New York Times/Siena College polls this week showed Democratic upstart Rep. Beto O'Rourke trailing GOP Sen. Ted Cruz by 9 percentage points. The polls are only the latest to show O'Rourke at a disadvantage in the red stronghold despite massive fundraising and Democratic enthusiasm.

In the race to succeed swing Republican Sen. Jeff Flake in Arizona, a new survey shows GOP Rep. Martha McSally leading Democratic Rep. Kyrsten Sinema. The race is one of Democrats' two best chances to pick up a Republican-held seat. Still, Sinema has a slight lead in an average of recent polls, according to RealClearPolitics.

The House

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  • Nonpartisan forecasters generally consider at least 68 House districts competitive. Republicans overwhelmingly hold the seats that could flip: for instance, the Cook Political Report lists 29 GOP-held seats as toss-ups, while it puts only two Democratic-held seats in that category.
  • Democrats have about an 8-point edge on an average of recent generic ballots, which ask respondents which party they would prefer to control Congress, according to FiveThirtyEight. The party's advantage has barely budged since the beginning of the month.
  • Democrats have about a 78 percent chance of taking control of the House, according to FiveThirtyEight's forecast. It projects an average gain of 35 seats for the party — which would comfortably put it in the majority. Democrats' chances have climbed from about 74 percent on Oct. 4.
  • Cook Political Report lists Democrats as favorites to flip 15 GOP-held seats, and Republicans with an edge to take one Democratic-held seat, due to redistricting. If Democrats take those 14 seats, they only need to flip nine more out of the dozens on November's battlefield that the site lists as toss-ups or "lean" Republican.
  • Sabato's Crystal Ball gives Democrats an edge in 210 districts. Therefore, the party would have to take eight of the 28 seats the site classifies as toss-ups.
  • Inside Elections, another nonpartisan forecaster, sees the most likely outcome as Democrats gaining 25 to 35 House seats in November, enough to seize a majority.

Forecasters saw a handful of House races moving toward Democrats in recent days.

Cook tweet

Both Cook Political Report and Sabato's Crystal Ball moved Kansas' 3rd District contest to leans Democratic. A New York Times/Siena College poll found Democratic challenger Sharice Davids leading GOP Rep. Kevin Yoder by 8 percentage points.

Florida's 26th District moved to the toss-up category at Cook. Republican Rep. Carlos Curbelo is defending his seat against Democratic challenger Debbie Mucarsel-Powell. The Democrat's standing in polls of the district, which Hillary Clinton carried in 2016, has improved recently.

Cook also shifted a rare battle of two incumbents in Pennsylvania's 17th District to "likely" Democratic. Due to redistricting, Democratic Rep. Conor Lamb faces Republican Rep. Keith Rothfus. Lamb, who has strong favorability ratings and a fundraising advantage, leads by double digits, according to a Monmouth University poll released Wednesday.