Pretty much every major Democrat of the past three decades has spoken out in favor of tough border security measures...including border walls! Just listen to them in their own words (and read their quotes below):
"Illegal immigration is wrongplain and simple. When we use phrases like 'undocumented workers,' we convey a message to the American people that their Government is not serious about combating illegal immigration, which the American people overwhelmingly oppose. Above all else, the American people want their Government to be serious about protecting the public, enforcing the rule of law, and creating a rational system of legal immigration that will proactively fit our needs rather than reactively responding to future waves of illegal immigration." -Chuck Schumer, 2009
"Operational control of our borders--through significant additional increases in infrastructure, technology, and border personnel--must be achieved within a year of enactment of legislation." -Chuck Schumer, also in 2009
"The American people need to know that, because of our efforts in Congress, our border is far more secure today than it was when we began debating comprehensive immigration reform in 2005. Between 2005 and 2009, a vast amount of progress has been made on our borders and ports of entry. This progress includes 9,000 new border patrol agents in the last 4 years [and] construction of 630 miles of border fence that create a significant barrier to illegal immigration on our southern land border." -Also Chuck Schumer, also in 2009
"While we need to address the issue of immigration and undocumented people in this country, we certainly don't want any more coming in." -Nancy Pelosi, 2008
"I believe we have very serious immigration problems in this country. As you heard today, sanctions against employers who hire illegals are nonexistent, our border is porous....I don’t know why we need millions of people to be coming into the country who will work for lower wages than American workers and drives wages down even lower than they are right now." -Bernie Sanders, 2007
"All Americans, not only in the States most heavily affected but in every place in this country, are rightly disturbed by the large numbers of illegal aliens entering our country. The jobs they hold might otherwise be held by citizens or legal immigrants. The public service they use impose burdens on our taxpayers. That's why our administration has moved aggressively to secure our borders more by hiring a record number of new border guards, by deporting twice as many criminal aliens as ever before, by cracking down on illegal hiring, by barring welfare benefits to illegal aliens. In the budget I will present to you, we will try to do more to speed the deportation of illegal aliens who are arrested for crimes, to better identify illegal aliens in the workplace as recommended by the commission headed by former Congresswoman Barbara Jordan. We are a nation of immigrants. But we are also a nation of laws. It is wrong and ultimately self-defeating for a nation of immigrants to permit the kind of abuse of our immigration laws we have seen in recent years, and we must do more to stop it." -Bill Clinton, 1995
"I voted numerous times when I was a senator to spend money to build a barrier to try to prevent illegal immigrants from coming in. And I do think you have to control your borders." -Hillary Clinton, 2015
"If making it easy to be an illegal alien isn’t enough, how about offering a reward for being an illegal immigrant? No sane country would do that, right? Guess again. If you break our laws by entering this country without permission, and give birth to a child, we reward that child with US citizenship and guarantee full access to all public and social services this society provides — and that’s a lot of services. Is it any wonder that two—thirds of the babies born at taxpayer expense in county-run hospitals in Los Angeles are born to illegal alien mothers?" -Harry Reid, 1993