What exactly is an emotional appeal here?
I had assumed that the op meant "emotional appeal" to mean someone attempting to appeal to someone else's sense of compassion/empathy using gratuitous emotion- not
just appealing to someone's compassion/empathy, but doing so in such an over-the-top fashion that it's blatantly manipulative and even coercive. (That Sarah Maclachlan ad is a good example.)
It's entirely possible to appeal to someone's compassion by presenting
just the facts- and it seemed to me like the point many people were making here is that it's far more effective to appeal to compassion where that's the case. Going overboard with it is precisely what shuts compassion off for a lot of people. As soon as you imply someone 'should' be feeling something,
counterwill kicks in and shuts empathy off.
But if "emotional appeal" here means simply
any appeal to someone else's compassion/empathy- no matter how logically presented, how void of leading emotion, if the goal is ultimately to appeal to someone's sense of fairness not in a manipulative way- then I'd agree liberals use it more.
[If however "emotional appeal" does mean to appeal to someone's irrational sense of righteousness (eta: e.g. devout faith in Scripture, and faith that it should apply even to people who don't follow that religion /eta), then it seems to me like conservatives are far more guilty- if only because I personally don't begin to understand that appeal, thus making it appear completely irrational/emotion-driven to me.]