An Illinois court on Monday threw Rahm Emanuel's name off the Chicago mayoral ballot, possibly ending the former White House chief of staff's bid to lead his hometown.

By a 2-to-1 vote, an appellate panel overturned two previous decisions and ruled that Emanuel is not eligible to run because he moved to Washington D.C. for two years.

"We conclude that the candidate neither meets the municipal code's requirement that he have 'resided' in Chicago for the year preceding the election in which he seeks to participate nor falls within any exception to the requirement," said the majority opinion by justices Thomas E. Hoffman and Shelvin Louise Marie Hall. (Read the court decision here.)

The decision came less than a month before the Feb. 22 election, and the chairman of the Chicago board of election commissioners said he will do as he was told: "We're going to press with one less candidate for mayor," Langdon D. Neal said in a statement.

Emanuel has been considered the front-runner in the race, having far outraised his opponents.

An attorney who argued on Emanuel's behalf told the Chicago Sun-Times that they will immediately appeal the decision to the Illinois Supreme Court. Emanuel himself sounded confident during a Monday afternoon press conference.

"I have no doubt that we will, in the end, prevail at this effort," Emanuel told reporters at Chicago's Berghoff restaurant. "As my father always used to say, 'Nothing is ever easy in life.' Nothing is ever easy. This is just one turn in the road."

Emanuel's campaign can take some measure of hope from the blistering dissent by the appellate panel's third member, Justice Bertina Lampkin. Lampkin wrote that the majority opinion was based on legalistic distinctions she termed "indefensible," "ill-reasoned and

unfair" and "completely erroneous."

Emanuel clearly did not give up his Chicago residency when he relocated temporarily to Washington, Lampkin insisted. "[T]he majority promulgates a new and undefined standard for determining candidate residency requirements despite the plethora of clear, relevant and

well-established precedent that has been used by our circuit courts and election boards for decades," she wrote. "It is patently clear that the majority fails to even attempt to define its newly discovered standard because it is a figment of the majority's imagination."

Lampkin wrote that, at most, the court should have sent the case back to the city's election board for a rehearing. "Merely saying the candidate 'unquestionably does not satisfy' its newly-minted standard, when the ink of its creation has barely dried on the paper, cannot be a proper substitution for providing a hearing," she wrote.

And Lampkin accused the majority of a "careless disregard for the law shortly before an election for the office of mayor in a major city," concluding: "The majority's decision disenfranchises not just this particular candidate, but every voter in Chicago who would consider voting for him."

The decision came in a case brought by two voters who objected to Emanuel's candidacy because he rented out his Chicago home and moved his family to Washington. "If the house had not been abandoned by the whole family ... we wouldn't be here today," attorney Burt Odelson told the panel of judges, all three of them Democrats.

Odelson until now has had little luck trying to keep Emanuel off the ballot. The Chicago Board of Election Commissioners and a Cook County judge had both ruled in favor of Emanuel, a former congressman, saying he had not abandoned his Chicago residency.

Emanuel is one of several candidates vying to replace Chicago Mayor Richard Daley, who did not seek a seventh term. Emanuel moved back to Chicago in October after he quit working for Obama to campaign full-time.

The three main other candidates running -- former Sen. Carol Moseley Braun, former schools President Gery Chico and City Clerk Miguel del Valle -- have been critical of Emanuel during the race, calling him an outsider who doesn't know Chicago.