Sure you can. Both the pro-life movement & traditional marriage proponents have been very effective, passing DOMA in the 90s and outlawing partial-birth abortion. Also working on public opinion which shows more people support traditional marriages and younger people being pro-life.
If a Republican disregards life and supports homosexual marriage, how are we to trust him on other issues that matter? Giving benefits to homosexual couples and funding Planned Parenthood isn't fiscal conservatism.
You don’t have to support abortion or gay marriage.
Focus on fiscal issues doesn’t mean you don’t have those other values. It’s not either/or.