Update Wednesday 3/21/12 8:23 AM: The final count was 47% for Romney and 35% for Santorum. Romney will take at least 41 of the Illinois delegates. You can watch his victory speech and read the transcript at WaPo.
Update 8:40 PM ET: For those of you counting delegates, here’s the latest tally. Illinois delegates aren’t counted there yet.
Update 8:33 PM ET: That didn’t take long. Fox News just called the race for Mitt Romney. Bret Baier just reported that it’s too soon to say how the delegates will be split. The delegates are split up by congressional district, so we’ll have to wait for all of the districts to report. Santorum didn’t get his paperwork into all of the districts, so some he could win but not get the delegates. The economy was the biggest issue for voters in the exit polls. (Fox’s headline that they called it for Romney links to one of their earlier posts. Here’s their Illinois results page.)
Polls are now closed in Illinois and the Republican primary results are starting to come in. So far it looks like a big night for Mitt Romney. According to CBS News Romney is leading with 54%, Santorum is in second place with 29%, Gingrich has 10% and Ron Paul has 6%. Gingrich and Paul didn’t really campaign in the state. Santorum did, but polling showed he wasn’t going to do as well as it looked about a week ago, so he split for the east coast.
I’ll update this post as more results come in.