Okay, so four Repubs, not 2. Big deal.
Even Hillary and Obama voted for the bill, which was just before the 2006 midterms The elections resulted in the loss of Congress for the GOP. It was Kay Bailey Hutchinson who helped amend the law a year later that effectively neutered it. The Secure Fence Act was was passed for the optics it provided before the midterms. There is no real support for actually securing the border. It is just obligatory, meaningless political rhetoric.