Sarah Hall Ingram was in charge of tax-exempt organizations under Douglas Shulman. Her successor is Joseph Grant.
Douglas Shulman, a Bush appointee, was head of the IRS and was succeeded by Steven Miller. Steven Miller promoted Ingram to head Obamacare.
Shulman was a Dem and had been a big activist under Clinton. Bush just about knocked himself out trying to be “bipartisan” and it got him nowhere. He thought appointing a Dem to a (theoretically) apolitical position would show his good will. To them, it showed his weakness.