‍Republican parents are twice as likely as democrats to feel ok doing so.

1. 如果“复位”，去掉as ... as ...比较结构便可：
Republican parents are likely to feel ok doing so.‍

2. to feel ok 与 be likely 共同构成“合成谓语”，be likely 具有推测的“情态意义”，are likely to feel ok = may feel ok
3. doing so, 分析为“时间状语” 或“方面状语” 均可，分别相当于：while doing so 或 in doing so。