House: https://manifold.markets/lisamarsh/will-the-democrats-win-a-majority-i -> 30%

Senate: https://manifold.markets/BTE/will-republicans-take-the-majority -> 85%

Presidency: https://manifold.markets/BoltonBailey/will-a-democrat-win-the-white-house -> 45%

So the naive probability is probability is 10%. However, they're definitely correlated with each other, and the outcome where the House goes Republican and a Democrat wins the Presidency seems quite unlikely.