On Tuesday, voters will head to the polls in Illinois, which has the second highest delegate total of the Republican primary race so far. Here's what's at stake, how the process works and the current state of the race.
* Illinois sends 69 delegates to the Republican National Convention.
* Each of the state's 18 congressional districts accounts for a varying number of delegates, depending on how strongly that district voted for the Republican presidential ticket in 2008. Most districts have three delegates. Two each have two and two have four.
* Voters must be identified as pledged to a particular candidate or officially uncommitted. Voters are not required to vote for delegates that are pledged to support the candidate the voter voted for. A full list of candidate delegates by district is available from the State of Illinois.
* Twelve at-large delegates will be assigned at the Illinois Republican Party State Convention in June. These delegates attend the Republican National Convention unbound to any candidate.
* The remaining three delegates are party leaders and also attend the convention unbound.
* Illinois allows early voting. The early voting period was Feb. 27 to March 15. The Chicago Tribune predicted a low turnout based on a lower number of early votes this year compared to 2008.
* All absentee ballots must be postmarked the day before Election Day and must be received by the Election Authority within 14 days of Election Day.
* Three polls, all done in March, give Mitt Romney the lead. A Chicago Tribune poll released March 9 gave Romney a four-point lead over Rick Santorum, 35 percent to 31 percent. Two additional polls give the former Massachusetts governor a more comfortable lead. A Fox Chicago poll from March 14 put Romney ahead of Santorum 37 percent to 31 percent. A Rasmussen poll on March 15 gave Romney a lead of 41 percent to 32 percent. All three polls put Newt Gingrich in the mid-to-low teens and Ron Paul in single digits.
- Republican National Convention