There are some that will find his position wrong. But I strongly reject the characterization of his position as a "please-all-side" or unprincipled position.
You can personally believe that an embryo outside the womb is not "human", but still recognize that others disagree and therefore oppose public funding of the research in deference to those who have strong opposition.
In fact, that is the argument Bush uses when he opposes the federal funding for the research.
And you could call Bush's position "unprincipled" as well. He allowed federal money for research on lines that had already been "something-or-other"ed, that sounded like they were already dead. But if allowing research on embryos that will NEVER be used and are slated to be destroyed anyway is wrong, you could argue it is also wrong to KEEP funding research on embryos that are simply a step further along in that process.
Anyway, my point is that Mitt's position is a consistant one, even if wrong to some people. And so long as he would veto requests for federal money, he should do what we need him to do. Bush isn't running around making speeches opposing the research at a private level (except cloning), and Romney apparently won't either (except for cloning).
So anybody who isn't up in arms over Bush's position shouldn't have a problem with Romney's position, IF you believe he is being truthful about it.
Bush made it clear that the destruction of embryos for research is immoral, and he therefore allowed the federal funds only for those 60 stem cell lines derived from the few embryos that had already been killed in 2001. Bush opposes "further destruction of human embryos," and has said, "There is no such thing as a spare embryo. Every embryo is unique and genetically complete, like every other human being. And each of us started out our life this way. These lives are not raw material to be exploited, but gifts."
Meanwhile, Romney sees nothing morally wrong with killing embryos for research. He touts an opposition to federal funds for ESCR merely to appear to be against something that he in principle favors. Not only is that called "trying to please both sides," it's deceitful.
That is true. The allowing of research on the already existing lines is akin to finding utilitarian use for murdered bodies, and I do find that unprincipled.
Nevertheless, Bush has maintained an opposition to the further destruction of embryos. That is the thing that distinguishes him from Romney, who sees no intrinsic value in embryonic human life.