what do I do?

PokerStars No-Limit Hold'em Tourney, Big Blind is t100 (6 handed) converter (http://www.selachian.com/tools/bisonconverter/hhconverter.cgi)

If CO folds or calls I'm moving in, but after he moves in I wasn't sure what to do. Call and lose, I'm all but out. Call and win, I'm winning the whole thing. What do you guys think?

MP (t815)
CO (t2100)
Hero (t2150)
SB (t2820)
BB (t4040)
UTG (t1575)

Preflop: Hero is Button with K/images/graemlins/diamond.gif, A/images/graemlins/spade.gif.
<font color="#666666">1 fold</font>, <font color="#CC3333">MP raises to t815</font>, <font color="#CC3333">CO raises to t2100</font>, <font color="#666666">3 folds</font>.

[tigerite]

I've seen this done by all sorts of ace-rag crap, and sometimes KQ, KJ, certainly not only pairs. It's a tough one though, if you have a read on him of being a bit of a donk and overplaying ace-rag and seeing loads of flops etc, or calling all in (I am guessing he's got the 2000 chips somehow, right?) then it's surely a call.