Well, I think there are a lot of flaws in your reasoning here, but I'll try to do my best to address your question.

First off, the idea that everyone is born equal is more of a legal principle rather than a belief that literally everyone is born with equal traits. There are absolutely people of every ethnicity that are born with crippling deficiencies, or extremely beneficial genetic traits.

Secondly, there really isn't any speciation between different sorts of humans that's occurred in the last 60 thousand years or so when we all sort of popped up in Nigeria and started making our way across the world. We all originated with those first humans in Africa. There are certainly traits that are more common in certain ethnicities that negative, but it'd be really hard to quantify what's objectively good or bad. But either way even the variation among different ethnicities make it hard to say "oh this ethnicity is bad and this one is good" more like this ethnicity is more or less likely to produce this certain trait. You could probably fairly say that "a lot of ethnicity X have Y problem" but the problem with racism is it's that it is tied with the idea that "because some of X ethnicity have Y negative trait, that means they are all bad or inferior."

I hope that clarifies my opinion on that.

Now I want to address the idea that secularists 'come from the left.' This is a silly notion because it's not like the left produces secularists, you can find plenty of nations/regions on the planet that are more liberal than the US but still have very high religious populations, who have pretty left leaning opinions. Also, don't forget that a lot of libertarians are atheists/secularists. Finally, it should be pretty apparent that the republicans, in general, vastly support the political agenda of christians at the expense of other religions and atheists. It's only natural that an atheist would tend to shy away from the party that makes decisions largely based on the idea that there is a god and actively works against the spread of atheism and its agenda.

Anyway, to summarize, people aren't created equal in general, but they do all have, and all deserve to have equal treatment and protection under the law. And to use mental shortcuts to classify entire ethnicities as inferior/superior is lazy, inaccurate, and probably very detrimental to society as a whole.