Even if he did, that would not translate into Congrssional support for Tancredo.
How? You just got through insisting that it wouldn't deport any illegals, so that wouldn't destroy the economy. As for new arrivals, they would come in legally. If the conditions imposed for granting guest-worker status are too strict, it won't make anything worse, because the illegals would then continue to come in as they do now. Besides, those conditions can be loosened later on if needed, just as long as illegals don't qualify.
political suicide for the Republican Party
How? By carrying out the will of 75%-80% of the voting public? Yeah, that's always been the death knell for politicians.
Even if he did, that would not translate into Congrssional support for Tancredo.
Of course it would, which is the exact reason why he's not doing it, or even not arguing against it. He knows that even having it part of the public debate at all is dangerous, from his perspective, because that's the one the public would instantly flock to.