The Center for Voting and Democracy makes projections on the winning party and percentage in U.S. House races based on a simple observation:  the result of Congressional elections is largely determined by the partisan composition of the district, which can be measured by the presidential vote in the last election.

After the September 30 release of our report in a press conference covered live on C-SPAN, we obtained partisanship data for House districts in Alabama, Nebraska and New Hampshire and decided to remove the four races in which two incumbents were running against each other in the general election.  Our final number of projections was 333.

These following figures uses data available as of Wednesday, November 6 at 9pm.  As final election results become available over the next few weeks, we will revise these figures.

We will adjust our projections for November 2004 only when we obtain partisanship data for the 50 districts that currently lack such data, and when an incumbent does not run for re-election.
 

Accuracy of Projected Winners (data as of Wed, Nov 6 9pm ET)

Projection	Margin	Races	Correct	Percent	Errors
Landslide	>20%	194	194	100.0%
Comfortable	>10%	101	101	100.0%
Win	Win	38	38	100.0%
Total		333	333	100.0%

Accuracy of Projected Winning Margins

Projection	Margin	Races	Correct	Percent	Errors (actual margin)
Landslide	>20%	194	190	97.9%	4 races only won by comfortable margins: CA-51 (18.4%); ID-1 (19.6%); MS-2 (10.3%); PA-11 (13.2%)
Comfortable	>10%	101	99	98.0%	2 races won by less than comfortable margins:  SD-1 (7.8%); TX-23 (1.9%)
Win	Win	38	38	100.0%
Total		333	327	98.2%