Republicans are moving fast to squelch Justin Amash's rebellion against Donald Trump before his conclusion that the President "engaged in impeachable conduct" -- the first by a GOP lawmaker -- can gather momentum. But Democrats who want a more hardline strategy against the President are seizing on the Michigan congressman's sudden intervention to pile pressure on their own leaders for tougher action. Amash's act of conscience on Saturday sparked immediate speculation over whether a tiny leak in the Republican dam could grow into a torrent of support running away from the President.