Has he had a chance on those issues himself? Plus, we know he takes into account public perception of ideological rulings. It may push him toward liberal rulings if conservative is picked.

Also, Trump may have to nominate a moderate. They don't have time to have nominations shot down, and with the slimmest of margins (McCain is ailing), republicans may try to woo a handful of moderate dems. My guess is that will be impossible with the intense pressure, so at the very least they'll need every single repub to hold the line.