SOURCE
Catholic.com - College of Cardinals

DEFINITION
The Cardinal Electors are those members of the College of Cardinals who have not reached their 80th Birthday on the day on which a Pope dies. That is, if they turn 80 years of age before the Pope dies, or on the day he dies, they are ineligible to vote in the Conclave to elect his successor. However, if they turn 80 years of age the day after the Pope dies they are eligible. Interestingly, even if they cannot vote they can be elected. As of Wednesday, April 20, 2005, there are 183 Cardinals from 66 different countries, 117 of whom are eligible to vote and 66 of whom are ineligible.

DEFINITION: The Cardinal Electors are those members of the College of Cardinals who have not reached their 80th Birthday on the day on which a Pope dies. That is, if they turn 80 years of age before the Pope dies, or on the day he dies, they are ineligible to vote in the Conclave to elect his successor. However, if they turn 80 years of age the day after the Pope dies they are eligible. Interestingly, even if they cannot vote they can be elected. As of Wednesday, April 20, 2005, there are 183 Cardinals from 66 different countries, 117 of whom are eligible to vote and 66 of whom are ineligible.

SOURCE: Catholic.com - College of Cardinals