For decades, the size of the U.S. House of Representatives has pitted state against state in a fight for political power after each census.

That's because, for the most part, there is a number that has not changed for more than a century — the 435 seats for the House's voting members.

While the House did temporarily add two seats after Alaska and Hawaii became states in 1959, a law passed in 1929 has set up that de facto cap to representation.

It has meant that once a decade, states have had to face the prospect of joining a list of winners and losers after those House seats are reshuffled based on how the states' latest census population counts rank. How those seats are reassigned also plays a key role in presidential elections. Each state's share of Electoral College votes is determined by adding its number of House seats to its two Senate seats.

For most of the House's history, however, states did not lose representation after the national head count's results were released. Generally speaking, as the country's census numbers grew, so did the size of the House since it was first established at 65 seats by the Constitution before the first U.S. count in 1790.