Anyone who has had even one class in political science or American history and retained anything from said class should be aware that:
Regardless of which party; winning presidential candidates allmost always pander to their base during primaries (which consists of several different special interest factions within their party) and then switch to a more moderate stance during the general election and change their mode of operation (sometimes drastically as evidenced by Obama's 180 on the middle east wars etc) once assuming office and receiving their security briefing. Once elected they allmost always get picked on by those who supported them from those special interest groups for not doing what they promised their base they would do as they take on the responsiblity for running the country.
In the case of the republican party in recent decades an evangelical special interest group has risen to more prominence than it previously held, partly due to America straying away from its original moral standards over time due to a variety of factors and partly as a counter swing against several decades of whats perceived as liberal and atheist pressure against religion in schools, the media, and government.
Bush Jr was the first and only President to gain office who pandered support from the evangelicals of his party as any kind of recognized group and he didn't do diddly to make American into anything even close to what some anti-religious special interest groups or atheists feared of him in any way shape or form. He did; as described above, just what every single of President has done once in charge.
One can logically expect that if another president is elected in similar fashion (even a Muslim one) it will most certifiably not result in even the remotest move to change the USA's Constitution, its laws in general or its government in any way shape or form away from the guarantee of religious freedoms expressed by our founding father's for we their prosperity to keep and maintain.