I think it would play right into the media's hand if the Legionaires BOO him. MediaCrats will then have license to depict the audience as partisan, ala the Swiftees.
The better approach would be to stay firmly seated, arms crossed, with a "show me" expression on their faces. Polite applause any time he mentions the valor of our armed services. Total silence when he addresses his own exploits and anti-war activites---no applause, no booing...no reaction at all.
It would be bee-U-T-ful!
There will be no booing. They need the senator's vote on veteran's issues.
He'll get the same tepid reception he got at the VFW. is what I perdict.