MILWAUKEE — Democrats pushed liberal platforms on immigration, education and other issues while slamming President Donald Trump at a generally friendly town hall held Thursday by the nation's oldest Latino civil rights organization.

Four candidates — Julián Castro, Elizabeth Warren, Bernie Sanders and Beto O'Rourke — took the stage at the annual convention of the League of United Latin American Citizens, LULAC, vying to be the person who will be named the Democrats' nominee when the party returns to Milwaukee for its 2020 convention.

The candidates addressed a range of issues but immigration got some heavy focus in part because of an expectation that the administration will launch a round of immigration raids, targeting 2,000 families, beginning Sunday.

They accused Trump — who was due in the city Friday to push for passage of the United States-Canada-Mexico agreement — of trying to win re-election by terrorizing the Hispanic community.

"It makes no sense to make a policy based out of fear," former Housing Secretary Julián Castro said. "I'm not going to make policy based out of fear. I’m going to make policy to stand up for people who need a voice right now."

Castro also took a couple of swipes at some within his own party.

Castro said Jeh Johnson, who served as homeland security secretary under President Barack Obama, was wrong to call his proposal to change illegally crossing the border from a misdemeanor crime to a civil violation "tantamount to open border policies." He also criticized rivals who have not adopted that proposal.

"Secretary Johnson is wrong. Vice President (Joe) Biden is wrong and congressman O'Rourke is wrong," said Castro, adding he made the proposal to guarantee that migrant parents would not be incarcerated and separated from their children. "We are not going to have that in this nation in the years to come if I am president. I will not abide by it. I won't stand for it; we are not going to do it."

Warren unveiled her immigration plan just minutes before Castro addressed LULAC as the keynote luncheon speaker. Her plan includes the proposal, first made by Castro in his plan, on decriminalizing illegal border crossings.

Warren zeroed in as well on Trump's announcement Thursday that he'll send government agencies to gather data on the citizenship status of people in the country after dropping efforts to get a citizenship questions added to the census.

"This is not about trying to find out real information about citizenship and non-citizenship in America," Warren said. "This is about trying to stir up more hate. To try to get more people excited. Donald Trump has one big message to the American people, if there is something wrong with your life, if there is something that is not right, blame them."

Backstage at #LULAC2019, @JulianCastro & @ewarren embrace — he says “I was happy to see your immigration plan”, she says “Well, it has a lot of Castro”. #Friendship2020 — Natalie Montelongo (@natimontelongo) July 11, 2019

O'Rourke, responding to a question, said that immigration raids make the country less safe, because it makes immigrants fearful of reporting crimes, testifying in trials and generally participating in civic life. He pressed for greater scrutiny of Border Patrol saying that while he's grateful for their work, the job they do "is not license to mistreat people or act with impunity as we have seen throughout the history of the Border Patrol."

The candidates addressed other issues, some in responses to questions from the audience, including better pay for teachers, climate change, returning deported veterans and making college tuition free.

Sanders gave a definitive "no" when he was asked whether he would allow people to keep their private insurance. "Americans do not love their health insurance companies," Sanders said. He said the country needs to move to Medicare for all. "That will be achieved by millions of people standing up to insurance companies and drug companies, he said.

"In America today we have 34 million people who have no health insurance. We have even more who are underinsured and that hits the Latino community particularly hard," Sanders said.

Two others candidates, Tulsi Gabbard and Marianne Williamson, made appearances at the other panels held during conference, Michael Bennet was to participate Friday. Jill Biden, wife of presidential candidate and former vice president Joe Biden, was at the conference's opening day.

Trump also was invited but had not responded by Thursday. LULAC planned a march in downtown Milwaukee Friday to protest the administration's detentions of migrant children.

LULAC: "Our community is under attack"

Created by U.S. citizens of Mexican descent in 1929, LULAC promoted patriotism and assimilation to defend against discrimination and to counter perceptions of Mexican Americans as un-American.

Over the decades, LULAC has waged many civil rights battles to win equity for Latino schoolchildren, veterans, workers and eventually, immigrants.

The organization went into recovery mode last year after its former president, Roger Rocha, backed some of the immigration demands of Trump as Congress was negotiating immigration legislation. A June 15 LULAC treasurer's report stated that although expenses had been reduced, the organization was not raising enough revenue or and was not receiving commitments from corporate sponsorships as it had in the past.

But the group’s CEO Sindy Benavides told NBC News the report is based on last year's fundraising. LULAC has bounced back and is in a stronger position financially at this moment than it was at the same time last year, she said.

LULAC's relevance has been helped by the Trump presidency.

“We wish we were out of business. We wish after 20 years of transforming the community we were not in existence,” Benavides said. “But we are as relevant today as we were in 1929. Our community is under attack.”

She ticked off a list: immigrant family separations, the treatment of children at the border, the failed hurricane response in Puerto Rico, the effort in Texas to purge voters, moving the only polling place in Dodge City, Kansas to the outskirts to make it harder for Latino residents to vote, Trump's insistence on the census citizenship question and the use of pesticides while farmworkers are in the fields.

“We find ourselves every single day making sure the community is protected,” Benavides said.

Over the holiday weekend, LULAC’s president offered a $25,000 reward to anyone with information leading to the arrest, indictment and conviction of any Border Patrol or Immigration and Customs Enforcement agent who has abused children, migrants or refugees in their custody.

Eyeing Wisconsin's Latino voters

In Milwaukee, the state's largest city, about 6.9 percent of the population is Latino, having edged past the state's African American population, which is about 6.7 percent.

LULAC President Domingo Garcia said on Thursday that the group plans to spend about $300,000 in Wisconsin to try to increase the share of registered voters who are Latino from 6 percent to 10 percent.

"It’s a historical crucial moment," Garcia said. "We’ve never had a president who looked at Latinos as the enemy, as the other, like we’ve seen with this president."

The Midwestern state figures large in the political landscape. After years of Democrats winning the state in the presidential race, Donald Trump won the state and its 10 electoral votes by about 22,000 votes, helping tip the race for him. Since the election, some have criticized Hillary Clinton for failing to spend time in the battleground state.

Democrats have reason to believe they can bounce back, particularly after Tony Evers defeated incumbent Republican Scott Walker in the 2018 gubernatorial race. In his first legislative session, Evers attempted to restore driver's licenses and offer in-state tuition to immigrants in the country illegally through the state budget. Those items were stripped from the budget by the Legislature's Republican majority.

Wisconsin does not collect racial information when residents register to vote so John Johnson, a research fellow at Marquette School of Law, analyzed turnout in wards based on race.

In wards with a Latino plurality of voters, the number of votes cast by Hispanics tripled from .2 percent to .6 percent. That's not a big share, but in a battleground state where elections are won on razor thin margins, the increase can make a difference in a race, Johnson said.

Last year, turnout of Latino registered voters in plurality Latino wards rose 14.5 percent — from 49.9 percent to 64.4 percent. That compared to a jump from 64.5 to 68.8 percent for voters in black plurality wards and 66.7 to 78.7 in white plurality wards.

More important, although the total number of votes cast in the wards with a plurality of Latinos grew by 24 percent, from 12,400 votes in 2014 to 15,400 in 2018, the number of votes for Walker in those wards shrank.

"All increases in voting benefitted Democrats," Johnson said.

JoCasta Zamarripa, a Democrat and the first Latina elected to the state Assembly, said her Milwaukee district is heavily Latino but continues to report the lowest turnout in the state. She said she has worked on increasing Latino voter turnout in the district as has LULAC, but she has not seen not consistent and substantial investment from candidates and the party.

"I'm imploring my own party to spend the money and invest the money to educate voters and get them to the polls," she said.

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