(CNN) Thousands of activists and allies poured into Madison, Wisconsin, on Thursday as part of a massive rally against legislation that protest leaders described as "racist" and "anti-immigrant."
Called "A Day Without Latinos and Immigrants in Wisconsin," the protests center on two pieces of legislation -- one, AB 450, would ban so-called "sanctuary cities" in Wisconsin, while another, SB 533, seeks to prevent local government from issuing ID cards to undocumented immigrants.
AB 450 recently passed the Assembly and is now expected to be considered by the upper chamber, while SB 533 has been approved by both and is headed to the desk of Republican Gov. Scott Walker. The governor's office did not immediately respond to an email asking if he plans to sign it into law.
Voces de la Frontera, one of the organizing groups, touted on its website "work stoppages, business closures and student walk-outs" in support of a broader effort to kill the bills and make a showing of immigrant economic power.
The author of AB 450, State Rep. John Spiros, a Marshfield Republican, rejected the characterization of his bill as "anti-immigrant," telling CNN he wrote it in response to the high-profile shooting death last summer of Kate Steinle. The 32-year-old San Francisco woman was allegedly killed by Juan Francisco Lopez-Sanchez, an undocumented immigrant and felon who had repeatedly re-entered the country after multiple deportations.
"After I saw that Wisconsin had three 'sanctuary cities' -- Madison, Racine and Milwaukee County -- I went to work and said, 'How can we do something to make sure we don't have another San Francisco?'" Spiros said. "That's truly what the basis was ...This bill is not there to split up families. It's not an anti-immigration bill."
Madison Mayor Paul Soglin, a Democrat, has denied that his city is a "sanctuary city."
But opponents of "sanctuary city" and ID bills view the current fight in much broader and consequential terms.
"This battle is giving us the opportunity to build a statewide structure to organize the Latino vote that will challenge any candidate who is anti-immigrant in 2016 and beyond," said Christine Neumann-Ortiz, the executive director of Voces de la Frontera, in a statement. "Wisconsin's fight reminds us that Latino and immigrant workers are willing to flex their economic power to send the message that they will not stand idly by while politicians try to pass laws that threaten their families and take for granted their labor."
The group said buses and caravans from 19 cities around the state were expected to help fill the streets of the capital. By early afternoon, the City of Madison Police Department tweeted a crowd estimate of 14,000 people.
"Walker, escucha, estamos en la lucha," some protesters chanted in Spanish -- "Walker, listen, we are in the fight" is the English translation -- according to a tweet from WISC-TV's Jessica Arp.
On Twitter, protesters used the hashtag #daywithoutlatinos to share images and information from the marches and their gathering inside the statehouse, while others dialed it up to tag expressions of solidarity.