Here is a response to my very recent post “Evangelicals Hopes for a Conservative Supreme Court Rest in the Hands of Someone Nearly Incapable of Telling the Truth.”
Voting on prospective Supreme Court nominees is a bit of a Hail Mary pass in several ways. First, as you note, there’s the question of will the president come through? (Conservatives weren’t too thrilled with Harriet Meiers, eg, and if the appointment had come earlier in the Bush administration, they may have gotten her.)
Second, will the justices actually deliver what conservatives want? Chief Justice Roberts is persona non grata with conservatives ever since the ACA decision. Scalia authored Smith, which has caused all kinds of headaches.
The record on abortion and homosexuality is even dodgier. Roe v Wade was authored by a Republican appointee, and 5 of the 7 justices in the majority were appointed by Republicans. Lawrence, which struck down state laws enforcing moral norms, was also authored by a Republican appointee, and 4 of the 6 justices voting in the majority were appointed by Republicans. Obergefell also was authored by a Republican appointee.
That doesn’t mean it isn’t a rational choice to vote for whoever the Republican candidate is, in the hopes that he or she might appoint satisfactory judges (and in the fear a Democrat won’t–though 100% of Clinton’s and Obama’s appointees voted in the majority on Hosanna-Tabor, the most critical religious freedom case in a generation).
But, given the spotty track record, the idea that it is mandatory or obligatory for Christians to do so seems questionable in the extreme. Especially so when so many other things about the candidates are decidedly not equal.