Conductor Resha Taylor directs passengers boarding Amtrak's Southwest Chief in Union Station in Chicago, Illinois. Scott Olson/Getty

Illinois just took a huge step forward in its push to bring high-speed rail to the state.

A resolution passed by Illinois state senate on Sunday urges Congress to invest $2.5 billion in high-speed rail and instructs the Illinois Department of Transportation to conduct a “ridership analysis” for possible high-speed rail.

The study of potential ridership is key, in order to attract funding from both public and private sources, according to Richard Harnish, executive director of the Midwest High Speed Rail Association.

Last September, Illinois Governor Pat Quinn announced a $102 million capital investment to improve Illinois railroad links between Chicago and St. Louis.

Rail service between the two cities currently reaches 110 mph on specific sections of track, thanks to the initial investment last year, but infrastructure remains the biggest hurdle for the state’s rail advocates.

Chicago has been a hub for rail freight since the 1800s, but all the tracks between Chicago and St. Louis are owned by freight companies, including Canadian National and Union Pacific. Amtrak, the only passenger rail in the region, must pay for the right to operate its services on the privately owned tracks.

Similar high-speed rail projects are underway in in the Northeast, Texas, and California.