A Question About CSS

I wonder if someone can answer me a question, and possibly explain how to do something.

At the moment I’m updating my creative writers blog; one section of the blog gives information about current contests. The information is given in the following format:
Name Of Competition
Brief Description
Closing Date
Entry Fee
Organizers Contact Info

What I’m aiming to do is make the Name Of Competition stand out a little and I’ve done that by adding the following style to my custom style sheet:
/*Competition Header Text*/
h3.competitions {
font-size: 15px;
font-family: arial,sans-serif;
font-weight: 400;
font-style: normal;
color: 008000;
}
Within WordPress my opening line would look like this:
<h3 class=”competitions”>Name Of Competition</h3>

My problem, if you can call it one, is this. Every sixth line I’m going to have to start writing <h3 class=”competitions”>Name Of Competition</h3> and to be honest if you are publishing eight or ten competitions that’s a bit of a pain.

So what I’d like to know is is there a way I can automate/semi-automate this process;
for example could you put the name of the style h3.competitions into say where you have your paragraph and header tags then just select and click on h3.competitions just as you would on paragraph.

Are there any plugins that will help me do this

As I said the above is just a ‘for example.’ I know very little about css and how to control it. Any advice on how I can short cut the writing out of the whole style would be appreciated