What is the Religious Right?

What is the Religious Right and what does it have to do with the Republican Party? also, are the Deomcrats or Republicans more against church and state? it seems to me that republicans want to ban gay marriage, are against abortion, secularism, etc. my govt. professor told me that the republican party is ful of christian fundamentalists that want us to have a christian nation. i mean no offense to republicans or democrats. but i would like your input on this matter, please?