A MOJ Reader's Question. Any Thoughts?

[This morning, a reader of this blog sent me an e-mail messsage, the main part of which I have excerpetd below. The reader, self-described as a devout Catholic, asks an interesting question. Any thoughts?]

There is one issue ... that I'd appreciate your thoughts on. Last night a
campaign ad that I'd never seen before flashed across my television screen. It
showed a succession of photographs of aborted fetuses with a running commentary
indicting George Bush for failing the pro-life cause. It was an ad for a
third-party presidential candidate whose name and party escape me now--but
who declared himself the *real* pro-life candidate, significantly more pro-life
than Bush.

It occurred to me that until now, many conservative Catholics had justified
their full-throated (and, indeed, not a little smug) support for Bush by
claiming that even though he is not fully pro-life he is more pro-life than
Kerry. They claim that they are, then, not only permitted but obligated to
vote for him. So what happens when an obscure third-party candidate appears on
the ballot who is ostensibly more pro-life than the president? By this logic it
would seem that we are obligated to vote for him. Your thoughts would be
appreciated -- on the blog or otherwise.