Complex sentence: The Republican Party gained 63 seats in the U.S. House of Representatives, recapturing the majority, making it the largest seat change since 1948 and the largest for any midterm election since the 1938 midterm elections.
Split into simpler sentences: The Republican Party gained 63 seats in the U.S. House of Representatives, recapturing the majority. This was the largest seat change since 1948 and the largest for any midterm election since the 1938 midterm elections.