(CNN) House forecast: Democrats will win 229 seats (and the House majority) while Republicans will win just 206 seats. A Democratic win of 205 seats and 262 seats is within the margin of error.

Senate forecast : Republicans will hold 52 seats (and maintain control of the Senate) next Congress while Democrats will hold just 48. Anything between Republicans holding 47 seats and 57 seats is within the margin of error.

Republican hopes of holding the Senate look as bright as ever. Thanks to clear Republican advantages in North Dakota, Tennessee and Texas in our forecast, the Democratic path to a Senate majority is currently blocked. All of those races are within the margin of error, but they aren't razor tight.

For 2020 presidential implications, however, the forecast has good news for Democrats. President Donald Trump was able to win in 2016 because he broke the Democratic stranglehold on the Midwest. Specifically, he took Iowa, Michigan, Ohio, Pennsylvania and Wisconsin. Without these states, he would have lost to Hillary Clinton. Trump also came close to winning Minnesota, which no Republican presidential candidate has done since Richard Nixon.

Democrats probably have to win back a good chunk of these states in 2020 to win the presidency.

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