The front-runners -- former state Rep. Robin Kelly, former U.S. Rep. Debbie Halvorson and Chicago Alderman Anthony Beale -- planned Election Day stops at train stations and restaurants in the district that spans Chicago's South Side, south suburbs and some rural areas. They were among 14 Democrats and four Republicans in the special primary, but the Democratic winner was expected to sail through the April 9 general election because of the heavily Democratic region.
Beale planned to vote at a school in Chicago, Halvorson was set to cast a ballot at a suburban community center and Kelly voted early.
Voters haven't seen an open primary since 1995, when Jackson first won office.
Turnout at the polls was expected to be low, and candidates and election officials braced for a possible winter storm that could dump up to six inches of snow on the region and complicate Tuesday's logistics. Election officials said they were in communication with streets and sanitation workers about making sure pathways to polls were kept clear.
In Chicago, fewer than 2,800 voters, or roughly 2 percent or registered voters in the district, cast early ballots. In suburban Cook County -- the bulk of the district's voting population -- it was nearly 2 percent. The last time the Chicago area had a special primary election for Congress was 2009 after Rahm Emanuel left his seat to take a job as White House chief of staff. Roughly 18 percent of registered voters in the district spanning North Side neighborhoods voted. In suburban Cook County, the percentage was far lower.
Guns and ethics were on the minds of voters, and both were main issues on the campaign trail, particularly as Jackson's legal saga played out in federal court. He pleaded guilty to illegally spending $750,000 in campaign money on personal items and faces prison time. The son of the civil rights leader is the third consecutive congressman from the district to leave office under an ethical or legal cloud.
Still, gun control became the top issue on the campaign trail, including at candidate forums and television ads.
Independence USA, the super PAC of New York City Mayor Michael Bloomberg, poured more than $2 million into the race for anti-gun ads in support of Kelly and against Halvorson, a former state lawmaker and one-term congresswoman. Kelly supports a ban, but Halvorson does not.
"Gun control, we need it," said retiree Angela Craig, an undecided Chicago voter. She had supported Jackson in the past but didn't feel like she got enough time to weigh the candidates.
Jackson resigned in November after a months-long medical leave. He pleaded guilty early this month to charges that he misspent $750,000 in campaign money on lavish personal items, including a Rolex watch and furs. His departure created a rare opening in the district.
Sophia Tareen can be reached at http://twitter.com/sophiatareen