About this chart race
In 1910 the House was an East Coast and Midwest institution. New York led with 43 seats, ahead of Pennsylvania (36), Illinois (27) and Ohio (22); California had just 11. Because the House has been fixed at 435 seats since then, this is a zero-sum race — every seat one state gains, another loses.
New York's decline is the long arc of the chart. It peaked at 45 seats in the 1930 and 1940 apportionments, then fell at almost every census to just 26 by 2020. Pennsylvania walked the same road, 36 down to 17, and the wider industrial belt — Ohio, Illinois, Missouri, Michigan — shed seats decade after decade.
California is the mirror image. It climbed from 11 seats in 1910 to 20 by 1930, overtook New York for first place after the 1970 census, and reached 53 before slipping to 52 in 2020 — the first seat it had ever lost. Texas (18 to 38) and Florida (4 to 28) rode the same Sun Belt wave, passing New York to take second and third.
By the 2020 apportionment — the map in force for the 2026 midterm elections — the largest delegations are California (52), Texas (38), Florida (28) and New York (26), with Pennsylvania and Illinois (17 each) and Ohio (15) next. Arizona's rise from 1 seat to 9 and Nevada's from 1 to 4 show how far the country's population has shifted south and west.
This animated ranking shows how seats in the u.s. house of representatives changed across 50 series between 1910 and 2020. The bars re-order themselves as the years advance, so overtakes are visible as they happen rather than hidden inside a table. Use the list on the left to choose exactly who competes, drag the slider to jump to any year, or open the table view to read the underlying numbers.
As of 2020, California leads with 52 seats.
Included in this race
California, New York, Texas, Pennsylvania, Florida, Illinois, Ohio, Michigan, Missouri, Massachusetts, New Jersey, North Carolina, Georgia, Indiana, Wisconsin, Virginia, Kentucky, Iowa, Washington, Tennessee, Minnesota, Alabama, Oklahoma, Arizona, Mississippi, Maryland, Louisiana, Kansas, Colorado, South Carolina, Arkansas, West Virginia, Oregon, Nebraska, Connecticut, Utah, Nevada, Maine, South Dakota, Rhode Island, North Dakota, New Mexico, Vermont, New Hampshire, Montana, Idaho, Hawaii, Wyoming, Delaware, Alaska.
Source
Data from U.S. Census Bureau — Congressional Apportionment. Every figure shown comes from this source — nothing is estimated or generated.
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