Reapply.
It is the only thing to do if you are serious about wanting to work there.
Yep.
Unless the new Ad says "Past applicants need not re-apply", then go again.
When I was looking around for a new job around about this time 2 years ago, I saw this ad for a job on the internet, (wasn't Seek, just some random site I'd never heard of, indeed.com I think it was called). Sounded something like I was looking for so I applied before the closing date for applications...
Then about a month or 6 weeks later, I saw the same job advertised again, with a new closing date, but I'd heard nothing about my first application... So I thought, do I bother applying again? Maybe none of the applicants they got were suitable so they have to re-advertise it? But I applied again anyway... Fast forward about 2-3 weeks more, and I get an email saying my application was unsuccessful... I was still employed elsewhere so I wasn't too fussed.... Another week goes by and I get a phone call from their HR Rep asking if I'm available for an interview! So what I worked out was the email I got was for the first application I lodged and the phone call was for the 2nd application... The place was re-structuring at the time and I'm guessing new people were responsible for recruiting initially or something like that...
So you just never know how it will play out. It's never going to hurt to re-apply. Hell, like Haynzy said, unless you think it would be detrimental, approach the company directly and reinforce on them, honestly, how keen you are to work for them.
Those of you who had Foxtel back in the day would remember Jabba the music host on channel V. I remember him once telling the story of how he got the job at channel V and he said when they asked him why he wanted the job and why they should hire him, he was brutally honest and said, because he was desperate and didn't have any other options so he couldn't afford a) not to get it, and b) to stuff it up if he did get it. And you know how it goes from there...