The Oct. 8 Sun-Times/We Ask America poll has Quinn ahead of Rauner 44 percent to 41 percent. The result in the broadest category was very similar to those of last week’s Reboot Illinois/We Ask America poll  (Quinn led 44-40) and a Rasmussen Reports poll conducted Sept. 24-25 (Quinn 44, Rauner 42). A key difference in the Reboot Illinois and Sun-Times polls was Rauner’s showing among Chicago voters. The Sun-Times poll had Rauner with nearly 19 percent of the Chicago vote. Rauner had 14 percent in Chicago in the Reboot Illinois poll. The goal for Republican candidates for statewide office is to pick up at least 20 percent of the vote in heavily Democratic Chicago.

The news for Quinn is mixed in the Sun-Times poll. By a margin of  41 percent to 36 percent, respondents chose Quinn as the candidate who most understands their everyday concerns. But Rauner was the choice when participants were asked which candidate they consider the reform candidate. Rauner had a 11 percentage point advantage over Quinn, 37-26. For 24 percent of participants, none of the three candidates (including Libertarian Chad Grimm) is a reform candidate. All candidates were reformers to 6 percent of respondents.

See the full results and read the Sun-Times analysis here.

From the first poll after the March 19 primary until early September, Rauner led Quinn in every poll, by double digits in some.

Rauner spent most of the Republican primary campaign bashing Quinn more than his primary opponents. Rauner began saturating the airwaves with advertising immediately after the primary and hasn’t let up since.

The incessant anti-Quinn message might explain some of Rauner’s big poll leads from March through September. Over the past month, Quinn’s advertising has become equally intense both in frequency and in its tone against his opponent.

The more recent poll results likely indicate that Quinn’s message is reaching its intended targets.

The chart below tracks polls from various sources dating back to March. Place your cursor over points on each line to see the source of the poll, date and result for that candidate. Note the precipitous decline in undecided respondents (yellow line) before and after the July 29 Mellman Group poll.

See all the recent Reboot Illinois/We Ask America polls: