Cook Political Report moves 20 House races toward Democrats

• Dave Wasserman, Cook's House editor, tweeted: "I can’t recall the last time we moved so many races at once, let alone in the same direction."

The state of play: Republicans need to pick up 18 seats to win the House back in 2020, but the tide is firmly moving against that hope.

• The changes moved four races from "lean Republican" to "toss up."

The big picture: Trump is notably trailing Joe Biden in the polls — by double digits, in many cases — less than four months before the election.

• Earlier this month, Cook forecasted that November could bring "a Democratic tsunami than simply a blue wave."

Worth noting: Not every race that moved in Democrats' favor is being labeled as a likely Democratic win, but Wasserman says that those races are "essentially an anti-Trump wave watch list."

Cook's moves (District: incumbent - change in rating) ...

• Ariz.-02: Ann Kirkpatrick (D) - Likely D to solid D.
• Calif.-04: Tom McClintock (R) - Solid R to likely R.
• Calif.-39: Gil Cisneros (D) - Lean D to likely D.
• Colo.-06: Jason Crow (D) - Likely D to solid D.
• Ind.-05: Susan Brooks (R), not running - Lean R to toss up.
• Kan.-02: Steve Watkins (R) - Likely R to lean R.

• Minn.-01: Jim Hagedorn (R) - Likely R to lean R.
• Minn.-03: Dean Phillips (D) - Likely D to solid D.
• Neb.-02: Don Bacon (R) - Lean R to toss up.
• N.C.-08: Richard Hudson (R) - Likely R to lean R.
• N.C.-09: Dan Bishop (R) - Solid R to likely R.
• Ohio-01: Steve Chabot (R) - Lean R to toss up.
• Ohio-12: Troy Balderson (R) - Solid R to likely R.
• Penn.-08: Matt Cartwright (D) - Toss up to lean D.
• Texas-03: Van Taylor (R) - Solid R to likely R.
• Texas-06: Ron Wright (R) - Solid R to likely R.
• Texas-21: Chip Roy (R) - Lean R to toss up.
• Texas-25: Roger Williams (R) - Solid R to likely R.
• Va.-10: Jennifer Wexton (D) - Likely D to solid D.
• Wash.-03: Jaime Herrera Beutler (R) - Likely R to lean R.