Illinois was easily won by sitting Vice President Al Gore by a safe margin of victory, unlike other states in the Midwest, such as nearby Iowa, Minnesota and Wisconsin, which Gore won, albeit by very small margins. Bush didn't perform terribly at the county level, as he obtained less than 40% of the vote in only three counties. Gore's key to victory was Cook County, home of Chicago, by far the most populous county in the state and one of the most populated counties in the nation. Gore won that county with almost 70% of the vote, his best performance in any county in the state. 
Technically the voters of Illinois cast their ballots for electors: representatives to the Electoral College. For this election, Illinois is allocated 22 electors because it has 20 congressional districts and two senators. All candidates who appear on the ballot or qualify to receive write-in votes must submit a list of 22 electors, who pledge to vote for their candidate and his or her running mate. Whoever wins the majority of votes in the state is awarded all 22 electoral votes. Their chosen electors then vote for President and Vice President. Although electors are pledged to their candidate and running mate, they are not obligated to vote for them. An elector who votes for someone other than his or her candidate is known as a faithless elector.
The electors of each state and the District of Columbia met on December 18, 2000 to cast their votes for President and Vice President. The Electoral College itself never meets as one body. Instead the electors from each state and the District of Columbia met in their respective capitols.
The following were the members of the Electoral College from the state. All were pledged to and voted for Gore and Lieberman: