Jackson's Republican opponent, Brian Woodworth, has argued that voting for Jackson will do harm to Illinois's 2nd district, since he has been absent for votes since June and it's unclear when he will return. But Jackson is nonetheless expected to win his seat again easily; polls from late October had Jackson up as much as 31 points over Woodworth.

Jackson recorded a robo-call in October that said he is "anxious" to return to work, but said doing so goes "against medical advice."

Jackson was seen in October in a bar in Washington, D.C., after which he returned to the Mayo Clinic. In October, it was reported that Jackson was being investigated for misusing campaign funds. He is also the subject of an ethics probe, which is examining whether Jackson sought to buy the Illinois Senate seat once held by President Obama.