Rich Miller, a fellow Sun-Times columnist and proprietor of the influential Illinois political newsletter Capitol Fax, commissioned an automated phone poll of Illinois voters last week on 2008 preferences.

On the Democratic side, Obama holds a two-to-one lead over Clinton, while the Republican race is wide open with Fred Thompson making a strong 3rd place showing:

Democrats
Obama 52.6
Clinton 24.6
Edwards 9.5
Undecided 6.9

Republicans
McCain 26.1
Giuliani 25.7
F. Thompson 17.7
Romney 10.2
T. Thompson 3.3
Undecided 17

Here's Miller on the poll's methodology:

The automated phone poll was conducted by "Ask Illinois," which has done a lot of polling for political candidates and interest groups and has a good reputation among insiders. The firm uses special technology to blast out hundreds of calls simultaneously and they contact huge numbers of people. In this case 3,509 hardcore Democrats and 3,761 Republicans responded to the poll, leaving us with an extremely low margin of error of +/- 1.18 to +/- 1.52 percent, depending on the question. Republicans and Democrats who indicated they intend to cross over to the other party next year were omitted from these results. The difference was statistically insignificant.