Fueling some of the most heated partisan fights is a dramatic realignment of congressional seats in which over half of the competitive districts have vanished over the past two decades.
Competitive House seats have been cut by more than half over the past two decades as Republican and Democratic voters drift further apart.
Since 1999, the quantity of swing seats plunged from 164 to 82, while hyper-swing districts eroded from 107 to 45, according to the latest Cook Political Report Partisan Voting Index (PVI). Most of that transformation was driven by voters moving more red or blue at the ballot box, rather than redistricting erasing competitiveness.
REPUBLICANS HOLD SLIGHT ADVANTAGE IN RACE FOR HOUSE CONTROL IN FIRST RATINGS FOR 2024 CYCLE
This stark hallowing out of competitive seats has favored Republicans. The GOP's arsenal of seats that lean five points or more in its favor surged from 150 to 189 since 1999, while Democrats' repository jumped from 121 to 164, according to the PVI.
"Elections have produced the biggest increase in strongly Democratic seats, while redistricting has swelled the number of strongly Republican seats," the index noted. "Republican state legislators have held the power to redraw far more congressional districts than Democrats."
Swing seats are defined as seats that rate lean Republican or Democrat within a margin of five points, while hyper-swing seats trend in either direction by a margin of three points.
The PVI scores a district's leaning by comparing its vote in presidential elections to the national vote. If a district is rated Republican +5, that means it went for the GOP by five points more than the national voting populous.
Over the past two decades, there has been an aggressive push in the redistricting battlefield to mold districts in a given political party's favor. But the Cook Political Report concluded that was less of a factor in the disappearance of competitive seats than voter polarization.
Since 1997, 58% of seats became more polarized due to shifts in voter tendencies, while 42% stemmed from apportionment, per the index.
"Though both play a role, urban/rural polarization has driven most of the competitive decline. In many minimally altered districts, the electorate has simply become much more homogeneous than it used to be," the group found.
CLICK HERE TO READ MORE FROM THE WASHINGTON EXAMINER
Coinciding with the decay in swing districts is a decline in the number of politicians who can overcome the partisan biases of their districts. Back in the 105th Congress that was in session from 1997 to 1998, 26 Democrats and 14 Republicans held seats that leaned toward the opposing party by three or more points, per the index.
Today, there are only five Democrats and four Republicans sitting in Congress who have achieved that feat.