If theism is simply belief in God or Gods, then I am clearly a theist. What flavor of theism is more complex, and I don't know the closest words, but I believe in a very Mormon structure of families of Gods going back in time perhaps longer than we can imagine. But look for a moment at this definition of atheism from Michael Shermer:
Of course, no one is agnostic behaviorally. When we act in the world, we act as if there is a God or as if there is no God, so by default we must make a choice, if not intellectually then at least behaviorally. To this extent, I assume that there is no God and I live my life accordingly, which makes me an atheist. In other words, agnosticism is an intellectual position, a statement about the existence or nonexistence of the deity and our ability to know it with certainty, whereas atheism is a behavioral position, a statement about what assumptions we make about the world in which we behave.
By this definition of atheism, belief in God would be better described as gnosticism (an intellectual position), while theism could be defined as acting as if there is a God. In this light I am almost an atheist.
1) I study to learn things. After starting on antidepressants, the experiences I had identified as messages from God vanished. I don't believe the messages I was given were bad. I don't believe this means no one has real messages from God. I'm not even sure mine weren't from God, I just realized it was a choice to believe they were. I had to seek for more reliable sources of light and knowledge in my life. I found some that work for me. They happen to rely heavily on publicly available data and analysis and shared human experience, and very little on publicly inaccessible experience of the Divine. In practice, I look for truth in ways very like an atheist skeptic.
2) I pray, but not because I expect God to specifically intervene in any way. Intellectually I accept that Heavenly Parents can intervene, but I expect any intervention to be human mediated and that any connection to the Divine will be unprovable -- even untestable. I'm willing to let others identify events and emotions as answers to prayer from God. They may be. But I don't expect it. So prayer is almost completely a human and personal form of meditation, for me. It would serve the same function in my life if God weren't listening. So I'm more atheist than theist in my prayers. I don't aspire to stay this way, but it is where I'm at.
3) I love church. I love being part of the community. I sustain my church leaders, and assent to the proposition that they are called by God and receive direct revelation. But all the evidence I see points to a human organization that is nearly indistinguishable in its function from many others. I value the details that are different, but I value them for their window on new ideas and their effects on people in this world. I value how sacred service gets us to do more mundane service than most others. I value how looking to our past and future families often makes us better in our current families. I value how the sacred and ritual settings unite people of different classes, races, educations. I value how missions open young people's eyes to many many things. I believe God has a hand in this, but most ways I act could as well be lived by an atheist.
4) I believe in the pervasiveness of agency. That it extends in simple forms to subatomic particles. Consequently, I believe in Gods who act pervasively through persuasion of all the matter that comprises our universe. In this way, acts of God are indistinguishable from acts of Nature. In seeing God's hand in all things, I approach the same functional position as seeing God's hand in nothing, and only the guiding forces of Mother Nature.
That describes how I am almost an atheist, but also interesting to me is how close many atheists are to belief in my God. Although Richard Dawkins and Sam Harris generally condemn religion, both allow for the possibility of God-like beings having created us. Since the Gods I believe in are within nature and evolved into the beings they are, Dawkins and Harris assent to the possibility of these Gods.
A cosmologist, Lee Smolin, has argued that our observable universe came to be through a process called cosmological natural selection. By this process, existing universes are spawned from massive black holes within other, pre-existing, causally connected universes. There is no conflict in cosmological selection with the evolved Gods I believe in, but Smolin doesn't invoke Gods in his explanation.
What these three men have in common is denying the likelihood or relevance of Gods, not the possibility of evolved, super-intelligent, creator beings. For example, Dawkins and Harris point to a lack of evidence for super-intelligent beings being involved with humanity. Smolin argues that universes optimize for creation of the largest numbers of black holes and new universes without intelligent intervention. Yes, each of these positions involves assumptions about things like what divine intervention would look like, or the ability of unintelligent processes to optimize black hole production, but they are reasonable assumptions and parsimonious explanations of human experience.
So why do I insist on going a step beyond? If I can explain existence as well without reference to God as with, why do I pose the questions: What would happen if intelligence could increase cosmic reproductive rates? (It would mean Gods are probable.) Assume there are Gods, what would be the significance of only allowing circumstantial evidence for their existence? What does it mean if we are akin to the Gods?
Why is it preferable to seek answers for these unanswerable questions rather than maintaining the functional position of atheism? Because I don't really live like an atheist. I live as if humanity can follow the example of older beings -- intelligent, compassionate, ancient creators.
So yes, I'm almost an atheist. I don't expect God to do the learning for me. I don't expect God to do the loving for me. I don't expect God to do the creating for me. I kind of expect that the Gods have already arranged my long life, but I'm certainly interested in how They did it. But I'm not an atheist because I act as if we can become Gods.
I act as if the atonement can bring humanity together into salvation -- a state that the Gods who went before us have found. A state that they invite us to join. A state that they inspire us to grow into. A state that can't be reached alone, and can't be reached without the grace of all the Gods who enter it. But a state of hope that all of humanity can live and grow in happiness, peace, knowledge, and creation forward into the eternities.
And really, any atheist who acts with hope for the long future of humanity, who seeks creation, and who acts as if our future requires love, compassion, and unity, such a person is a living witness of my God. Welcome to the fold.