Of course you can.  In the [Chern-Simons approach of Witten's][1] you can get knot polynomials for any compact simple Lie group.  (In fact, Chern-Simons theory for noncompact Lie groups is still not well-understood despite continuing progress, reviewed in a [very recent paper of Witten's][2].)  In fact, the knot polynomial associated to $\mathfrak{so}(3)$ is the Jones polynomial.


  [1]: http://projecteuclid.org/euclid.cmp/1104178138
  [2]: http://arxiv.org/abs/1001.2933