Joe Berrios vs. Fritz Kaegi

It takes a special set of circumstances to unseat a powerful county-level incumbent, but Kim Foxx showed it was possible when she defeated Anita Alvarez. But Alvarez had the weight of life-and-death tragedies and a phalanx of local and national activists bearing down on her. Berrios has the impressive but somewhat arcane Tribune/ProPublica Illinois reporting of Jason Grotto and the related research of University of Chicago prof Christopher Berry, on the fairness and impact of his office's work.

In limited polling, Kaegi has been way ahead of Berrios, and has managed to scrape off a bit of support from the Democratic establishment that Berrios has been a part of for so long. So it could end up being not just an upset, but one by a surprising margin.

Toni Preckwinkle vs. Bob Fioretti

The Cook County president is not one of the Democratic insiders that has abandoned the embattled Berrios. Her opponent, former alderman Bob Fioretti, recently released his own poll showing him just a point behind Preckwinkle. Despite the beating she took over the failed pop tax, a loss would be a genuine shock.

Marie Newman vs. Dan Lipinski

This race has gotten national attention, and as such it's been written about pretty thoroughly. It's not that complicated, ultimately: Lipinski is a relatively conservative Democrat in a safe Democratic House seat in a party that's moved towards the left generally.

Oh, and whoever wins will be running against a literal Nazi, so it's kind of the safest Democratic seat in the country this fall.

Back in January, when Carol Felsenthal wrote about the race, Newman was way behind in polls but was generating big-name endorsements. But as Felsenthal pointed out, Newman's numbers improved considerably when respondents were informed about her stances. A recent poll by NARAL (which supports Newman) put her within a couple points of Lipinski. He's been a NARAL target for awhile, but the results are plausible, and so is a Newman victory.

Jeanne Ives vs. Bruce Rauner

Political analyst Nathan Gonzales tweeted this yesterday:

OK, OK, "closer than expected for a challenge to a multi-millionaire incumbent governor" is doing a lot of work. What's closer than expected? In January, Rauner had a 45 percentage-point lead on Ives. In February, another poll had the gap at 20 points. A recent automated poll released by the Ives camp–take it as you will–had her down to single digits.

It's not impossible? Bruce Rauner's strong approval among Republicans in a March poll from SIU was 17 percent. "Somewhat approve" was 38 percent for a grand total–of approval from his own party–of 55 percent. It drops to 49 percent among self-identified conservatives and 38 percent among born-again Christians. Primaries tend to be more ideologically stringent, so it's conceivable that Ives could get lucky.

Daniel Biss vs. Chris Kennedy vs. J.B. Pritzker

This one looked like a possible upset a month ago, with Biss looking strong, but a more recent poll put Pritzker up 19 on Kennedy and 20 on Biss. Then again, it had Pritzker leading "undecided" 35-31. Anything could happen, but that also includes everyone splitting the undecided vote and Pritzker winning handily,