Years of underfunding has led Illinois' unfunded pension liability to reach an estimated $83 billion. Sustaining that system is costing the state upward of 15% of all general revenue spending. Democratic Gov. Pat Quinn has faced political opposition for a plan announced last month to restore some solvency. Among the proposals (estimated by the governor to save as much as $85 billion over 30 years): raising the retirement age for a full pension to 67, increasing employee contributions and capping cost-of-living increases.