So what that Stephen Crabb voted against same-sex marriage?
As Prime Minister, Tony Blair and Gordon Brown both explicitly ruled it out, as did Ministers in both of their Governments, speaking from the Despatch Boxes of both of Houses of Parliament. Brown never did vote in favour of it.
Well into his time as President of the United States, Barack Obama was frankly opposed to it. Hillary Clinton's conversion to it has been even more recent, and that of Bernie Sanders has been scarcely less so.
One eighth of the current Liberal Democrat party in the House of Commons voted against it.
At least one Labour MP who voted against it nominated Jeremy Corbyn for Leader, has not recanted, and certainly will not be recanting.
The very left-wing predecessors of two other MPs who nominated Corbyn, and one of whom has just been appointed to the greatly improved Shadow Cabinet, voted against it.
One of those had organised John McDonnell's unsuccessful attempt to contest the Leadership when Blair resigned.
There are many reasons to bemoan and resist the prospect of Crabb as Prime Minister. But this is not one of them.