The march started out nice and easy from Union Park in Chicago, looking more like one of those mass fundraising walks than a political rally.
Spirited chants of "Si, se puede" -- loosely translated as "Yes, we can" -- swelled from the crowd now and again as various groups wearing similar T-shirts or hats walked together.
Among the many handmade signs and placards marchers carried:
"We also have a dream"
"Your homes need my work for more beautiful"
"Mexicans in Mexico should organize like Mexicans in US"
"Stop the Raids Now"
"Don't bite the hand that feeds you"
The smiling women of St. Patrick's Old Church handed out cups of water to the marchers.
Marching alongside women in head scarves, Rami Nashashibi, executive director of the Chicago-based Inner-city Muslim Action Network, said his group brought 40 members to "stand up for Latino brothers and sisters."
Workers from the Chicago Housing Authority watched the marchers go by from their office, with a sign saying "We Support You" hanging in their window.
Boyd Klingler, a financial services worker in a suit, watched the marchers from behind a police barricade. Asked what he thought, he gave a wry smile and said, "That there are a lot more Mexicans in Chicago than we thought."
At Lou Mitchell's, a longtime Chicago lunch spot, two regulars discussed the issues as the marchers walked by.
"People aren't doing what they should be doing," said Gary Williams, referring to a story he read about local police who knew illegal workers were in their town but did nothing.
"I see both sides," said Dennis Mogan, adding that there must be some sort of middle ground to solve the problem.
As marchers entered the Loop, a motley band of anarchists made a racket beating on street signs and bucket drums with their "No Borders" and "viva Anarchia" message. Most marchers didn't seem to know what to make of them and followed cautiously at a distance.