I would have if I had voted in the first election that I was old enough to, but I did not. I was just out of high school and my entire upbringing was in a retired military household, and my hometown environment was pretty hard-lock conservative. I started college as an environmental biology major, didn't deny the science, got the idea of environmental imperilment stuck in my head. I later switched and finished as an English major (a much less wise choice) but I had an LGBTQ academic advisor and professor that grew up in a similar background and personally helped me overcome some of my struggles in sort of seeing perspectives on social justice issues and whatnot, and I personally never believed in anything politically enough to argue about it prior to college, I just don't ever recall being offered any alternatives -- it was "just the way it was" for all I knew, and to be honest to my recollection, I can't remember there being such a heated notion of separation between conservative and liberal until the 2008 US presidential election. That is to say, I don't remember being taught that my biggest adversaries were home-grown liberals, and I could comfortably watch things like Daily Show with Jon Stewart and very easily sympathize with the topics and perspectives. I don't remember being really all that adverse to any type of media at all until my English major education got applied to the way I saw things, and the 2008 election made Fox News just look horrible.
Now I hold left-leaning beliefs and have voted in every election since 2008, but if I had never left my hometown and gotten educated the way I did as an adult, I don't think I would've really broken free of the conservative/Republican perspective, and I see that in a few friends that never went to college. I was pretty certain I was going to end up ROTC and join the military and have that whole path laid out ahead of me prior to going off to college, but oddly enough my dad forbid that myself or my brother repeat military careers -- we were to be educated and successful by other means according to his wishes, which we both complied with ultimately. But I did swing by my college's ROTC recruitment office a couple of times early on.
Anyway, there was a time I could have voted Republican but I never did, because I was just out of high school and didn't really know my place as an adult member of society just yet, and it just seemed like a burden to my 18-year-old self. Things have changed a lot since then, for me personally and for the country.
I know for sure that I'll never vote Republican for the remainder of my lifetime. There's been enough since just 2007/2008 during my own kinda political awakening for me to firmly know that their political leanings don't align with the way I idealize society.
EDIT: bolded my run-on garbage to identify that I have failed to retain notions of well-composed English, too. Dammit.