From a House source who is already in one of the leader camps:

Given that the two candidates already in the race have received commitments from a significant portion of the Republican Members, Shadegg, Pence and the conservative cause might better be served by putting one of the candidates over the top now. Like in every other election, candidates remember those who were with them early and support after the election is won is remembered for what it is, a day late. Shadegg in particular may be able to strengthen his position in the GOP leadership if he publicly supports one of the leading candidates, especially if he is capable of delivering a victory.