I'm going to jump in on this one....as one who has both been in a few races as well as one who commuted daily to work on a bike.
You need to get a bike that fits how you will be realistically riding your bike. Don't buy a bike because you think a certain style will automatically make you a matching rider or that you picture yourself as fitting the profile of a certain type of rider, or even what you think others will think of you because you chose a certain style. I would highly recommend a well rounded hybrid bike. You may think that your location is flat, but you will soon realize that smalls hills that you rolled over without thought in a car will be more noticeable on a bike. You will also find a few gears will make the overall ride more enjoyable. The slightly wider tires of a hybrid bike will roll better over rough roads, and the more upright riding position will be more comfortable on your back. Having good disc brakes will be good to ensure you stop quickly even in wet conditions, you also will find that motorists will be less than accommodating to cyclists. After a few years when you find that your riding is heading in a certain direction, then you will be ready to spend more money on a more defined bike type. Get something easy to ride and more rounded now.
Be sure to budget for a quality bike lock and a helmet. I would recommend a helmet higher than any other aspect related to cycling. When cycling, it's just a matter of time before you go down...you don't want to end up dead or mentally damaged because you didn't want to mess your hair or look uncool.