SPRINGFIELD, Illinois, May 21, 2005 (AP) -- Illinois lawmakers have voted to have the state sell off about $1 billion worth of investments in companies doing business with Sudan , part of a nationwide campaign to protest genocide in the African nation.

If Gov. Rod Blagojevich signs the legislation, Illinois would become the first state in the nation to pull investments from companies with Sudanese ties. Similar legislation is pending elsewhere, and Harvard University also recently announced plans to stop Sudanese investments.

The Sudanese region of Darfur has been the site of an upheaval where about 180,000 people have died since fighting flared in February 2003. An estimated two million others have been forced to flee the region.

The conflict erupted when rebels took up arms against what they saw as years of state neglect and discrimination against Sudanese of African origin. The government is accused of responding with wide-scale abuses against the African population.

Sen. Jacqueline Collins, who pushed the bill through the Illinois Senate with unanimous support, said she modeled her proposal on laws passed in the 1980s that put pressure on South Africa to end apartheid.

"This is a piece of legislation that really grew out of my belief that I had to take a moral stand," Collins said.

The governor is reviewing the legislation and does not have a position yet, spokeswoman Rebecca Rausch said.

Some lawmakers say selling shares of companies tied to Sudan could cost the state money on its investments while having little effect on foreign affairs.

Rep. Bill Black was one of 23 representatives to vote against the measure, which still passed the House overwhelmingly this week. He said it could be dangerous to use state employee retirement funds to make political statements - especially when Illinois has an underfunded pension.

"Every dollar we lose in investment income exacerbates the pension underfunding," Black said.

Companies that do business in Sudan include oil, agriculture and engineering firms. The country has proven oil reserves of more than 600 million barrels.