I think the question here is perhaps more about what 'believe' means.
If believe means 'give intellectual assent to' and then get on with your life independent from that assent, then the theory of evolution falls into that frame quite well, and a lot of people 'believe evolution' in that way. Probably the majority of those people have never thoroughly looked into the evidence themselves but have accepted what professional scientists have said on the matter.
Along with the intellectual assent to evolution goes a satisfying sense of certainty that thus 'God as creator' can be rejected, and this is convenient, since it allows morals and foundational values to be chosen by each individual and there is space for each one to be selfish in this way. This linking of moral values to scientific observation is an altering of the meaning of the word 'belief'. This is the second meaning of the word 'belief' and in this case 'belief' implies 'I will take action upon the basis of that belief'. This is the kind of belief which operates between humans; I believe she is telling me the truth, therefore I will trust her. It is not merely an intellectual assent.
So believing an intellectual theory about evolution does not allow a human being to escape from the question of what beliefs they use to interrelate to other human beings, but many people think that it does exonerate them in this way.
Between all humans there are common values, shared fundamentals of not harming others, of self sacrifice and love for family and children, of truth and justice and wrong and right. I tend to think that every human being was created with that inner knowledge of those values, which we generally describe as conscience; we often describe as 'inhuman' the behaviours which cross those boundaries.
Now I tend to think that God is the 'deepest common ground' between humans in this way; off the back of this I consider that Genesis is aimed at telling us that the myths of the beginning of time tell us that part of being human is to have an inner sense of being formed by God, of having a part of oneself which knows and relates to God, of having conscience and relationship with others...and the common paths by which the inner connection from a human soul to God got broken, the common rebellions and rebuttals of the human soul away from the demands of conscience, the common excuses for these failures and the common consequences of those refusals, the pain which ensues within the inner self.
For me, to say I believe in Creationism would mean that I considered that the Genesis stories contained truth of *that* kind, which truth I do actually find useful in my daily life in dealings with humans who do universally seem to me to fit that simple model of formation / conscience / failure / hiding; I find a common ground there and I find a meaning in considering God as Creator to have a meaning in terms of creating creatures who are capable of spiritual interaction, having a dual nature (both body and spirit). That makes sense to me.
The writings of Genesis are not intended as scientific writings; that style of writing was only developed in the last 200 years. That said, the order in which the items are created accords with scientific observations, and the word 'day' actually means only 'period of time'. It is remarkable to me that the ancients had so much science figured out, but I do not think they wrote in order that I might 'intellectually assent' to their 'scientific explanation'. I consider that they wrote in order that I might understand my own construction in relation to being both a body and a spirit, and that I might also understand how that construction can break down and what the consequences of that for a human being are in real life. And I find that helpful to my understanding and I also find it very practical advice in relating to people. I also find it helpful in relating to 'God' and it shapes the view of the God whom I believe in; not an authoritarian old man in the sky but a potter forming clay with feeling...something of that flavour is added to my understanding of God.
I do not think the two ideas of Evolution and Creationism are in competition, when considered carefully and giving the best possible light to each one. Further the implications of the comparison are shallow and tend to make people feel able to ignore moral demands. In that sense evolution has damaged people by becoming an excuse for rejection of God and thus of morality.
Believing in a Creator places moral demands on me which I find consistent with being a human being and I find that belief impels me to act, which is what a belief ought to do.
As a scientist I have looked at the Fossil Record and considered the blank patches. I have noted accurately the difficulties of time scales for experiments. I have looked briefly at the effects of altering DNA. The theory of evolution tries to put all these together. However I heard Dawkins speak a few years ago and he could not explain the formation of the first DNA nor the problem of consciousness. I accept evolution as the best theory that we have as scientists, a theory which is constantly being developed and modified and which is outside my field of expertise. I note that my belief here is intellectual, does not impact upon my life in any way and is only an assumption of the professionalism of others; to believe them is a courtesy to them as humans who have integrity. That, and no more than that.
I believe in evolution intellectually, without action, and from courtesy.
I believe in a God who created me and redeems me and with whom I walk in fellowship. This belief impels action. It is not the same *kind* of belief at all.
I have not voted in the poll. Either both or neither, in the way the question is phrased.