Sabertooth basically told Gheen just that on LibertyPost - which means Gheen can't just dismiss the criticism as coming from Free Republic. And Gheen blew off the advice. Which means, IMO, he's either clueless to the PR aspect of this issue or agrees with the fringe stuff he posts. Neither possibility speaks well of him as an asset to the anti-illegal immigration movement.
The third possibility is that he is a subversive with a hidden agenda of discrediting those who are honestly working to secure our borders.