"Let the states decide .... " ???
NO.
The right wants huge government and massive control over citizens.
Get government out of our private lives.
If between consenting adults and harms no one, government should not have any say in who you choose to marry.
Oh, the restrictions to daily life that republicans want to impose legislatively are dramatic and profound. They would have sweeping effects on the lives of millions. Criminalized abortion, religion in schools, criminalized sodomy, elimination of most protections against discrimination, private businesses and landlords being free to discriminate on any basis they wish, the removal of fundamental standards of clean water and air, massive tort reform that favors corporations to an almost ludicrous degree, sweeping changes to voting laws that make it more difficult for voters who don't favor republicans to vote, etc.
And they resent that the federal government won't allow it. Don't ever let a conservative bullshit you on 'small government' and 'getting government out of your life'. If they had the power, many republicans would legislate their morality on you in a heart beat.