I see that the Common's speaker John Bercow's wife is to stand as a Labour candidate for Westminster Council in the ward where they live. Malc asked the question via Twitter, will he vote for her? My response is it ain't necessarily so.
As anyone who knows my dating history knows the hardest vote I always seem to have to win at any election is that of my other half, whoever they may be. Either if I am merely campaigning or especially if I am standing I have always had to fight for that one vote, it probably has something to do with the fact that I've never (knowingly) dated a fellow Lib Dem supporter. In the 2003 election I actually sat there while my partner at the time went through the postal vote forms. As both the constituency and list seats for Parliament slipped out of my grasp I eagerly waited for the one for the council seat. In the Croftmalloch ward where we lived there were 4 candidates the Lib Dem one being Stephen Glenn. Would I manage to persuade that final vote to go to such a worthy and trustworthy candidate? After a fair amount of teasing it finally did, so I at least knew I had two votes on the day, if only because the preferred options weren't standing a candidate in our area.
It leads back to the point that even though you live with someone, share many aspects of your live with them, when it comes do to political philosophy you may not be able to swing their vote your way. It may be one of those things that you agree to disagree on. I personally always enjoy the fact that one of the toughest audiences I have to argue policy with is at the other side of the dinner table, sofa or bed. I'm not sure what would happen with my own political edge if my partner was of the same political persuasion, I get to rehearse certain arguments in defence of some of our stances (dependent on political allegiances of the OH) on an ongoing basis.
So to answer the question, I think John Bercow should vote for who he wants to vote for, whether that is his wife or the conservative opponent, or anyone else for that matter, its up to him. It is a secret ballot after all.
PS On that note there is recently a vacancy opened up for the position described above. Anyone with a keen interest in politics, prepared to put up with me in full out election campaign mode for the next few months grabbing 'us' time when it is available, may apply. A non-Lib Dem political affiliation is preferable, though not essential (maybe). ;)