The point of a political party should not be about winning elections, nor should it be about pandering to the voters. The point of a political party is to enact positive change to our nation, and that means moving the middle away from the middle. The left understood this very well, why do we not? By moving toward the middle and abandoning out core principles we deserve to lose each and every time.
I am not religious. I do not see the evangelical faction of the Republican party pushing God onto the agenda. I see them as pushing a pro-life and pro-family agenda and i have no problem with either of these. Even as a libertarian the government still has to protect its weakest members and maintain the most basic unit of our society and community.
Having said this, I think the party should push these on the State level. Abortion is not and should not be a federal issue. It has no place in our constitution and all powers not explicitly given to the feds in the constitution belongs to the state. We should leave it there.
I would say the same of marriage. Having said that, I also think marriage should be a church issue and make civil unions a legal issue. I personally think civil union legal rights should only be given to families (i.e. couples with kids), whether the couple is heterosexual or homosexual).
The party should continue to push for strong nation defense primarily on the national level. Other aspects of the Republican principles like small government, fiscal responsibility, economic opportunity, and personal responsibility apply equally to State and Federal levels.