I think it's important to point something out.
Namely, racism is "natural." -- however, that does not make it "rational", or "acceptable."
Basically every species practices racism.
Wolves will kill members from foriegn packs on contact.
Bees will systematically attack another hive that is too close. (Same with ants)
Chimps.. same
Ad nauseum.
The main reason behind this is that the presence of a foriegn group in the environment means reduced availability of resources. This is not a conscious decision, it is purely animistic. The bees don't detect the right pheremones, and BAM, foriegn hive members get swarmed, and wings bitten off. This is further reinforced with ants-- it was recently discovered that 2 colonies of ants on different continents got along just fine when introduced to each other, because they had the same pheremone group id. Got the right IFF? Welcome aboard!
The same is true in humans, but complicated by humans also being thinking beings. The instinctual impulse of "Other! SHUN!" Is biological. People do this automatically, and unconsciously all the time. "Girls only", et al. The problem is that people don't always take the next step, and actually evaluate the impulse.
There is no reason to shun somebody from a different culture or racial heritage, because resources are not scarce. Further, the shunning of such people only diminishes the capabilities of the greater whole. Diversity is an asset, not a weakness. It is thus irrational to indulge the instinct.
Humans developed this behaviorism during the hard periods of our evolution preceeding and durrng the iceage. In evolutionary terms, that was "yesterday". Our culture has advanced faster than our instinctual and biochemical makeup. Racism is "natural" for us, as it served a valuable function in the past. It no longer does. It needs to be supressed.
Being a racist isn't "evil". Being a racist is irrational. Being a willfull racist, fully knowing it is irrational is what is evil.
The usual basis for racism against hispanics comes in 2 flavors, for the most part.
1) I don't understand what they are saying, and that makes me feel theatened/disadvantaged. This must be stopped.
2) hispanics are (presumed) here illegally, and work outside the system, and take work at pay rates well below what other people need to survive, and thus poison the economic ecosystem. This must be stopped.
Or at least, that is the 2 most frequently tendered modes of rationalisation of the innately irrational impulse to be racist I have encountered. "It's not irrational, because X" (choose X above.)
If you remove those sources of rationalisation, only the "willfully evil" types of racism really remain, when people actually are mindful of their behavior. (Most racism is involuntary, from people not being mindful. Spreading awareness is the best way to combat this; not demonization.)
In both of the 2 cases, eventual integration is inevitable. Look at New York, and the Irish immigrant "problem". Doesn't exist anymore. Many are proud of being of irish decent in fact.
The same will eventually come to happen in places with hispanic immigrant "problems". It will just take time.
Be understanding of people who aren't knowingly being racist, and instead help them to not be by spreading awareness for them. They shouldn't be demonized the way willfully racist people should be-- they are simply doing what is "fully natural". They just need to be aware that the nature needs to be overcome.