The term religious has gotten a bad reputation over the past several decades. It has come to mean a person who sits in a pew and does nothing for the Lord, or a person that follows various rules by their own power. In general, it has come to mean a person who only worships the Lord in a false or superficial manner.
Here is the definition
re·li·gion /rɪˈlɪdʒən/ Show Spelled[ri-lij-uhn] Show IPA
noun
1. a set of beliefs concerning the cause, nature, and purpose of the universe, especially when considered as the creation of a superhuman agency or agencies, usually involving devotional and ritual observances, and often containing a moral code governing the conduct of human affairs.
2. a specific fundamental set of beliefs and practices generally agreed upon by a number of persons or sects: the Christian religion; the Buddhist religion.
3. the body of persons adhering to a particular set of beliefs and practices: a world council of religions.
4. the life or state of a monk, nun, etc.: to enter religion.
5. the practice of religious beliefs; ritual observance of faith.
The word was never meant to be a substitute for Christian. It has evolved to have some negative meaning of a lax attitude towards the Lord. Christianity is a more defined term than religion. That does not make the term evil. As Christians, our day to day life is a close walk with the Lord, not a set of things to do or not do.
The poll question was not well worded. Carpro had an interesting point of the percentage of Americans going to heaven, compared to those who are religious, a much broader catagory. Of course, that is a matter of opinion. If one considers the diversity of our country, and also considers the numbers not attending any church, plus those in church who do not really believe, I doubt the percentage is very high, What we are asking is the percentage that have a true relationship and faith in Jesus Christ. There are saved in every Christian faith, and lost on every church roll, including Baptist. On our best day, only half of the members show up. My guess is under ten percent. I think one person said in a related thread on Mormons, that we might be surprised who we see in heaven.