glossary

AAG (At-A-Glance): The list of every House, Senate, and Governor's race in the country, broken into those three categories. The list is updated from the beginning to the end of every election cycle. The At-A-Glances list every seat up for reelection, as well as the incumbent, challengers, previous % of the vote the incumbent received, as well as the PVI and current rating of the race. Each challenger has a numerical value, which denotes the following: (1) Announced candidacy or certain to run; (2) Likely to run; (3) Maybe; (4) Mentioned but unlikely.

Baseline Analysis: Done at the beginning of the cycle, this is the initial analysis of each House, Senate, and Governor's race in the country. Competitive contests are continually updated throughout the cycle.

Bottom Line: Our most up-to-date take on a race.

Current Outlook: Our current projections of how many seats a particular party will pick up in the House, Senate, and Governors races in the upcoming election, as well as how we see the Electoral Vote breakdown in the Presidential race.

Electoral Vote Scorecard: Similar to our race ratings, this chart plots each of the fifty states and the District of Columbia based on how the Cook Political Report projects they will vote in the 2008 Presidential Election. Like our race ratings, they are on a seven point scale: Solid, Likely, and Lean for each party, as well as Toss Up.

FEC Charts: These charts provide a look at the FEC reports for candidates this cycle.

House Summary: This chart provides a glance at the open seats and potentially open seats this cycle.

Poll Charts: An updated listing of the polls on various races. There are primary trial heat, and general election poll charts for House, Senate, and Governors races.

Partisan Voting Index: Otherwise known as the PVI, this index was developed for The Cook Political Report by Clark Benson and Polidata Inc. The index is an attempt to find an objective measurement of each congressional district that allows comparisons between states and districts, thereby making it relevant in both mid-term and presidential election years. While other data such as the results of senatorial, gubernatorial, congressional and other local races can help fine tune the exact partisan tilt of a particular district, those kinds of results don't allow a comparison of districts across state lines. Only Presidential results allow for total comparability. A Partisan Voting Index score of D+2.3, for example, means that in the previous two presidential elections, that district performed an average of 2.3 points more Democratic than the nation did as a whole, while an R+3.8 means the district performed 3.8 points more Republican than the nation.

Race rating: The Cook Political Report's current rating of a particular race. Each House, Senate, and Governor's race is given a rating based on a seven-point scale, ranging from Solid to Lean on each side, as well as a Toss Up rating. This chart provides a spectrum that analyzes the vulnerability (the chances of the seat switching parties) of the races up this cycle.

Our ratings are defined as follows:

Solid: These races are not considered competitive and are not likely to become closely contested.
Likely: These seats are not considered competitive at this point but have the potential to become engaged.
Lean: These are considered competitive races but one party has an advantage.
Toss-Up: These are the most competitive races; either party has a good chance of winning.