Its everyones right to vote to make a personal or political statement.
IMO this sort of decision is easiest to make when it does not have practical political consequences, as for example when no better outcome is possible no matter how you vote.
In this case, it may amount to deciding that I would prefer to achieve neither of two important political goals to achieving one of them, if doing so allows me to vote my convictions on both.
The youth of today who 'get' abortion also 'get' homosexual marriage.
Likely, that statement is correct.
However, its also the case increasing majorities of younger people oppose easy access to abortion and that increasing majorities of young people support gay marriage or civil unions in your terms above younger people increasingly dont 'get' abortion but do get homosexual marriage so the two beliefs dont in fact march in lockstep.
A lot of people on both the left and right find these trends difficult to accept (for example, many liberals refuse to accept that the increasing opposition to abortion can be real), but it is in fact what's happening.
Public votes AGAINST gay marriage are always in the majority
And that majority has been steadily eroding, especially over the last decade.
For example in 1990 polling was showing approval for homosexual marriage in California at around 25%, in 2000 Proposition 22 passed with 61% support, in 2008 Proposition 8 passed with 52% support, and the demography suggests that a narrow majority will favor its repeal by 2014, or 2016 at the latest.
Such demographics tell the story, in fact political demographers have produced estimates as to when the tide of popular opinion will turn in each state, on this basis the last group of reddest states will repeal such prohibitions in the early 2030s.
In fact, it likely wont take that long as its going to politically and economically inconvenient for the last holdouts to maintain such prohibitions once they are clearly in the minority.
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IMO, the practical political question that needs to bet answered is: To what extent does opposition to homosexual rights reduce the attractiveness of pro-life candidates to younger pro gay rights voters?
This may be a significant effect, or it may not.
AFAIK, no one knows the answer.
I question the backbone of anyone who says we should surrender while winning the war. Votes against Gay marriage are in the majority in EVERY election. Anyone who trusts liberal media polls of youth will trust a CNN presidential poll showing Al Gore and John Kerry winning. Only a RINO gives up character to be popular.
And that majority has been steadily eroding, especially over the last decade.
Only because the sheeple live in a state of learned helplessness. The left has managed to make the homosexuals a protected class. Once inside a voting booth, things change. People are allowed to speak freely.
Put homosexual marriage up for a vote in every state and see what happens when the PC police aren't allowed to get involved. Even the most liberal state in the union - California - voted it down twice!
I'd like to see states actually be allowed to vote on abortion as well. Things change behind that curtain. Left wing propaganda loses it's power there (which is why they always use liberal judges instead).