There are a few Protestants groups that still recognize the value of baptism and hold that it does in fact regenerate, they include, but are not necessarily limited to: Anglicans, Lutherans, Methodists and some Pentecostals.
Before responding to the Protestants that believe baptism does not save, I will post several Scriptures showing the importance and value of baptism.
Whoever believes and is baptized will be saved; whoever does not believe will be condemned.--Mark 16:16This verse clearly links baptism with the word "saved." However, in my experience Protestants will have 2 possible rebuttals to this: 1)the emphasis of Mark 16:16 is "belief," 2)this section is not part of the Bible.
To answer the first claim, to say the emphasis is 'belief' is just trying to ignore the fact baptism is even mentioned. This is more of a statement rather than a rebuttal. The fact is the sentence still reads "believers and is baptized will be saved." It does nothing to address the fact baptism is mentioned in connection to salvation.
The second claim is not very common since most Protestants still trust the KJV which includes this part of Mark 16. Once a Pentecostal minister told me this, then I later caught him quoting this same debated section of Scripture to lend support for speaking in tongues ie "speaking in new tongues" (Mark 16:!7). Even if, theoretically, this passage were an addition to Scripture, we do not rely solely on this passage to teach the importance of Baptism.Now another verse that shows the role of baptism in salvation:
"Repent and be baptized, every one of you, in the name of Jesus Christ for the forgiveness of your sins; and you will receive the gift of the Holy Spirit."-Acts 2:38Peter here is making repentance and baptism necessary for the forgiveness of sins. This verse is also very straightforward in stating baptism's necessity for the forgiveness of sins. In my experience there have been a few rebuttals to this. One is the ridiculous claim that is saying sins are "remitted" in the sense of a disease, and they may come back somehow. Another rebuttal is that the word eis means they have forgiveness because they repented and because they have forgiveness they can be baptized. The third claim is a more modern and extreme claim by hyperdispensationalists who assert that this was only for that time, and now we have a "dry baptism," since it was intended for Jews.
In response to the first claim, the word remission is found in some older bibles like the KJV and DRB, however, even then the word remission typically means forgiveness, in the Greek the word remission is also used in Mark 3:29 for the forgiveness of the eternal sin, for more on this see the question and answer page on question Q7.In response to the second claim, the word eis typically means "into" or "for." Their repentance and baptism causes their sins to be forgiven. The word is used about 1865 times in the New Testament, almost all the occurrences means "into" or "for."
In response to the third claim, Dispensationalism is false because Paul himself baptized people with water in Acts 19, 1 Corinthians 1, and Gentiles who were not proselytes to Judaism were explicitly baptized with water in Acts 10 by St Peter's order. There is no reason to believe they stopped or intended to cease water baptism. Also, the Christian baptism is not the same baptism as St John the Baptist since his followers had to be rebaptized with a Christian baptism in Acts 19.