Keeping ahead of broadcast trends

I can't remember when I first heard a broadcast journalist use ahead of, as in "the candidates are making their final appearances ahead of Tuesday's primary" but now I can't recall a broadcast when I haven't heard it.

Whatever happened to prior to, leading up to or even before? It's another example of how an innocuous term can quickly gain a foothold. (See metrics.)

Interestingly, political coverage also includes the more traditional use of ahead of, as in "Romney pulls ahead of the field."

Hmmm, we could do even better:

"Romney appears to be running ahead of the field ahead of next Tuesday's primary in his quest to be a head of state."

But I'm getting ahead of myself.