Yes, libertarian free will is quite popular.
The second question is a little bit harder to answer. As usual with such questions. A substantial part comes however from my experience around here, Christianforums. From people's post. The free will defense, for instance, is quite common.
Part from apologists. Platinga, and the free will defense. And doesn't WLC have something about free will in the CA, too? I could swear I remember something like this, I might have even posted a fragment from a clip where he said that. Do you recall anything like that?
And part from various other sources. The Catechism has something on free will, but you have to forgive me that I do not know at this moment what exactly it was. There is however a quote which I already posted on this forum here that does in no uncertain terms say that God has free will, and the context makes clear that it is libertarian. And the RCC is not to shoddy.
A goody, which is fairly easy to show, is the PhilPapers Survey here:
Preliminary Survey results | PhilPapers Surveys
The thing is, that when you filter for all faculties support amongst philosophers for libetarian free will is quite ... reserved:
Free will: compatibilism, libertarianism, or no free will?
Accept or lean toward: compatibilism 550 / 931 (59.1%)
Other 139 / 931 (14.9%)
Accept or lean toward: libertarianism 128 / 931 (13.7%)
Accept or lean toward: no free will 114 / 931 (12.2%)
When you filter for Philosophers of Religion the results look quite different:
Preliminary Survey results | PhilPapers SurveysFree will: compatibilism, libertarianism, or no free will?
Accept or lean toward: libertarianism 27 / 47 (57.4%)
Accept or lean toward: compatibilism 12 / 47 (25.5%)
Accept or lean toward: no free will 5 / 47 (10.6%)
Other 3 / 47 (6.4%)
57.4% is much higher. The caveat is that there are only 47 respondents, and we don't really know how many of those are Christians. However they are in the target faculty group (
Target departments | PhilPapers Surveys). Setting "population" to "all respondents" yields 177 respondents, with 49.2% pro LFW. Look at it yourself, and play with the settings.