Peter Fitzgerald Republican Barack Obama Democratic The 2004 United States Senate election in Illinois was held on November 2, 2004.

The inequality in the candidates spending for the fall elections – $14,244,768 by Obama, and $2,545,325 by Keyes – is also among the largest in history in both absolute and relative terms.

Five years later, when Ryan's Senate campaign began, the Chicago Tribune newspaper and WLS-TV, the local ABC affiliate, sought to have the records released.

Ryan went on to win the GOP primary on March 16, 2004, defeating his nearest competitor, Jim Oberweis, by twelve percentage points.

[8] Ryan was a proponent of across-the-board tax cuts and tort reform, an effort to limit payout in medical malpractice lawsuits.

Oberweis's 2004 campaign was notable for a television commercial where he flew in a helicopter over Chicago's Soldier Field, and claimed enough illegal immigrants came into America in a week (10,000 a day) to fill the stadium's 61,500 seats.

[14] Barack Obama, a member of the Illinois Senate since 1997 and an unsuccessful 2000 Democratic primary challenger to four-term incumbent U.S. Rep. Bobby Rush for Rush's U.S House seat, launched a campaign committee at the beginning of July 2002 to run for the U.S. Senate, 21 months before the March 2004 primary,[15] and two months later had David Axelrod lined up to do his campaign media.

[23] Obama touted his legislative experience and early public opposition to the Iraq War to distinguish himself from his Democratic primary rivals.

Obama succeeded in obtaining the support of three of the state's largest and most active member unions: AFSCME, SEIU, and the Illinois Federation of Teachers.

Hynes and multimillionaire former securities trader Blair Hull each won the endorsements of two of the nine Democratic Illinois members of the US House of Representatives.

[28] As the campaign progressed, the lawsuit brought by the Chicago Tribune to open child custody files from Ryan's divorce was still continuing.

[30] A few days later, on April 2, 2004, Barack Obama changed his position about the Ryans' soon-to-be-released divorce records, and called on Democrats to not inject them into the campaign.

[29] On June 22, 2004, after receiving the report from the court appointed referee, the judge released the files that were deemed consistent with the interests of Ryan's young child.

"[31] Although their sensational nature made the revelations fodder for tabloid and television programs specializing in such stories, the files were also newsworthy because of questions about whether Ryan had accurately described the documents to GOP party leaders.

Prior to release of the documents, Ryan had told leading Republicans that five percent of the divorce file could cause problems for his campaign.

[36] Farm broadcaster Orion Samuelson was prepared to accept the nomination but was forced to abandon those plans under a doctor's orders.

[38] Third, Keyes's lack of electoral momentum enabled Obama to focus on campaigning in more conservative downstate regions, an unusual move for an Illinois Democrat.

The Chicago Tribune published a scathing editorial, calling him "[t]he GOP's rent-a-senator" and sarcastically listing basic facts about local geography for a candidate they suspected had no familiarity with the area: "Keyes may have noticed a large body of water as he flew into O'Hare.

"I'm supposed to make a call that represents the congratulations toward the triumph of that which I believe ultimately stands for... a culture evil enough to destroy the very soul and heart of my country?