Sreedhar Potarazu, an ophthalmologist and entrepreneur, is the founder of Enziime , a software company focused on providing data science applications to assess health care delivery. He is the author of " Get Off the Dime: The Secret of Changing Who Pays for Your Health Care ." The opinions expressed in this commentary are solely those of the author.

In 2016, another barrier may very well be broken. All polls indicate that a woman or a Latino has a very good chance of being elected to be our 45th president.

But there is another barrier -- an important one in the eyes of the world -- that is almost certain not to be smashed. Barring an unprecedented political upheaval, the next president of the United States will be a Christian, just like virtually all of his (or her) predecessors. The only exceptions may have been Thomas Jefferson, who abandoned orthodox Christianity, and Abraham Lincoln, who often spoke of God and frequently quoted the Bible, but who never joined a church.

There are more than 300 million people in the United States, and 70.6 percent of them self-identify as Christians. But that percentage dropped dramatically -- by 7.8 percentage points -- over the course of seven years, and there now are roughly 100 million non-Christians living in the United States.

It's another symbol of the changing face of our country, but it has yet to be reflected at the top level of American politics. Will the United States elect a president who is not a Christian?

Few non-Christians have run for president

A Jewish Democrat, Joe Lieberman, and a Jewish Republican, Arlen Specter, have run for president, but neither succeeded in winning his party's nomination. Lieberman, who was Al Gore's running mate in 2000, was the only Jew ever to run on a national ticket. Bernie Sanders is running for the Democratic nomination in 2016 but he is trailing Hillary Clinton in the polls

As for all the other religions that are part of the American mosaic, the total number of major-party presidential candidates remains stuck at zero.

There is one Hindu in Congress: Rep. Tulsi Gabbard of Hawaii. There are two Muslims: Reps. Keith Ellison of Minnesota and Andre Carson of Indiana. There are two Buddhists: Rep. Hank Johnson of Georgia and Sen. Mazie Hirono. None of them has ever been so much as mentioned as a possible president.

I am a Hindu by birth and Indian by origin. I also was born in the United States, and I am proud to be an American. In my travels throughout the world, I have developed a deep respect and appreciation for every religion. I feel the same energy at the Church of the Nativity in Bethlehem that I do at the Balaji Temple in Tirupati, India. I feel it at both the Wailing Wall and the Dome of the Rock in Jerusalem.

But while this energy has enlightened me, it also has left me thinking about my country's image. The fabric of America has changed dramatically in the last half century, and I'm concerned that our politics are not keeping up with the change.

Other nations more flexible

One has to wonder why the United States has not evolved as quickly as other democracies. Indira Gandhi became prime minister of India in 1966; Golda Meir became prime minister of Israel in 1969 and Margaret Thatcher became prime minister of the United Kingdom in 1979. Yet the United States, a prime model for democracies in the world, has never had a woman president.

One has to wonder why India, a nation of nearly 1.3 billion people, 79.8 percent of whom are Hindu, has had a Sikh prime minister (Manmohan Singh) and a Muslim president (Abdul Kalam), yet for more than a century and a half the chief executive of the United States has always been a Christian.

And this is not a trivial matter. The United States, like no other country in the world, has opened its doors to immigrants. For nearly a quarter of a millennium, it has truly been the land of opportunity. People from all cultures have come here seeking a haven where their hopes and dreams can come true. Or at least most of them.

Donald Trump's suggestion that the United States ban all Muslim immigrants caused an uproar across the world, because it flew in the face of what the United States believes and what people throughout the world believe America stands for: universal acceptance of all people, regardless of their faith or cultural background.

As our country becomes more diverse, it needs to persuade both its own citizens and all those who hope to become citizens that it will always be a land of limitless opportunity for everyone.

Our message has always been one of acceptance. It's ironic that we profess to believe that everyone is created equal, but at the end of the day, when push comes to shove, our leader is inevitably a Christian. And this does not go unnoticed in many parts of the world. How do you get the world to believe what you say when your actions speak louder than words?

Sreedhar Potarazu asks: Would today's Americans put a non-Christian president in the Oval Office?

Sending a message to the world

Last week, people throughout the world celebrated a glorious event, the birth of Jesus Christ. Even in predominantly Hindu India, Christmas is a national holiday. Perhaps it's time for our schools to start calling off classes for other holidays to build more awareness, as in New York City, where schools are closed for holidays like Rosh Hashanah and Eid al-Adha.

Schools may start calling off classes for Diwali as well, to educate our children from an early age that all religions matter, and that they all are to be respected and celebrated. Maybe this will pave the way so that 20 years from now, the United States will see a president who is Jewish, Hindu, Buddhist or even Muslim.

The demographics of the United States have changed dramatically, but religion remains the elephant in our room. In a poll taken three-and-a-half years ago , 40% of Americans said they would not vote for their party's presidential nominee if he were a Muslim. If the nominee were an atheist, 43% wouldn't vote for him.

One has to wonder what those percentages would be if the poll were taken today. Why are Americans willing to break down some barriers, but not all of them? Why is a candidate's religion a make-or-break issue for so many citizens of a nation that professes to embrace respect and equality for all faiths?

This election cycle has presented us with our most diverse group of candidates ever: two women (Hillary Clinton and Carly Fiorina), an Indian-American (Bobby Jindal) and an African-American (Ben Carson). But diversity stops at the door of the church. All four, and all the other 2016 candidates, are Christians , with the exception of Sanders, who is Jewish.

We cleared a big hurdle in 2008. We may clear another in 2016. But religion may well be the biggest hurdle of all, especially while we are waging a war against religious extremists who are hell-bent on destroying Western civilization.

But the question nevertheless must be asked: Can we, the citizens of the greatest democracy on earth, elect a president who is not a Christian? And if we do, can we then evolve to the point that the president's religion isn't an issue ... isn't even worth mentioning?

If the answer is yes, it will send a message to the rest of the world that we truly are the "shining city on a hill," where every parent can tell every child that we live in a country that breaks through every barrier, and that he or she truly can grow up to become president of the United States.