You basically had Protestants shrink far more drastically in the USA compared to Catholics and Mormons. With the rise of the religious right, it became easier for Protestants to accept some traditional Catholic beliefs in return for political support.
That said, American Protestantism is a clusterfuck of different churches with wildly different beliefs. The beliefs may be slowly coming together, but there is no firm Conservative Christian Canon yet and cracks are already starting to form with abortion and divorce.
You basically had Protestants shrink far more drastically in the USA compared to Catholics and Mormons. With the rise of the religious right, it became easier for Protestants to accept some traditional Catholic beliefs in return for political support.
That said, American Protestantism is a clusterfuck of different churches with wildly different beliefs. The beliefs may be slowly coming together, but there is no firm Conservative Christian Canon yet and cracks are already starting to form with abortion and divorce.