Estimates are that the law will disenfranchise one in 10 eligible voters - mostly people of color, students, seniors and low-income voters.
The St. Louis rally was held simultaneously with other rallies in Kansas City and Jefferson City, the Missouri state capital.
Reacting to Republican efforts to suppress voting, the African American community and the AFL-CIO are mounting a massive effort to promote balloting.
People's World pamphlet "Democracy at the Crossroads: Class Warfare and the 2012 Elections" is available to order or to download.
If one were to believe the commercial media coverage, it would hard to get around the conclusion that Texas voters are lazy, mean, and not very bright.
The campaign to oppose voter photo ID represented all three of Minnesota's major political parties.
The right wing of U.S. politics is not just attacking unions and workers' rights but the very foundation of our system of government, says Sen. Tom Harkin.
While states like Florida are trying to make it harder and harder to vote - at least for some - the state of Washington has taken another tack.
Florida has been in the eye of many natural storms. The Sunshine State is now in the eye of a man-made voter suppression storm.
That more than met the requirement of at least 385,253 signatures from half (44) of Ohio's 88 counties.