The hopefuls seeking Chicago's open mayoral seat and all 50 slots on the City Council have now turned their nominating petitions over to city election officials. But that doesn't mean the candidates are guaranteed to make onto the February 22, 2011 ballot.

WBEZ's Steve Edwards runs down the rules that campaigns are using to try and boot opponents out of contention or play defense against someone else's ballot challenge. There are plenty of places for campaigns to allege wrongdoing or incorrect procedure: Nominating petitions must be notarized, bound, and in numerical order; signers must be registered to vote, live in the appropriate district for non-citywide races, and only sign one petition; and those circulating petitions must be at least 18 years of age and appear before a notary, among other requirements.

While the first day of hearings won't take place until December 6, all challenges are due in by tomorrow. "That means campaigns are in engaged in a frenzied review of petitions ... The whole enterprise is a bit reminiscent of water polo or synchronized swimming:  the real action happens underwater, out of view," Edwards writes. Check out the full piece here.

Ballot challenges aren't idle threats or mere stalling tactics. Ben Joravsky of the Chicago Reader wrote late last year that they end up helping and protecting incumbent politicians. He detailed how a challenger to State Rep. Deb Mell (D-Chicago) got kicked off ballot and a supporter of State Sen. Kwame Raoul (D-Chicago) contested the petitions of Raoul's challenger in the Democratic Party primary. The ballot battles that emerge tomorrow -- perhaps most significantly for Rahm Emanuel -- matter.