Democrats hope to ride a wave of liberal enthusiasm and anti-Trump sentiment to a House majority in the midterm elections in November. All 435 House seats are up for grabs, but only about 48 seats are considered competitive (rated tossup or leaning toward one party), based on an average of estimates from three organizations.
Flipping 24 seats is not unprecedented, or even uncommon.
There have been swings of 24 seats or more in half of the midterm elections since 1994. The last time Democrats took the House with that kind of swing was the 2006 midterm election, when they picked up 32 seats.