The RCC has many teachings that are consistent and coherent. They are buried deep in the vastness of the body of works produced by the copious number of academics the RCC had at its disposal. They also had a headstart. Most of this doctrinal development is lost to the Reformed Church. Luther was quite happy to be Roman Catholic and fully expected to be reinstated after being acquitted for raising what he felt was justified objection to the blatant malpractice prevailing in the church. That's not how hierarchies work, as he found to his chagrin.

The first reformers, or the group who had the French label "Protestant" applied to them, had a very narrow agenda, list of objections . However, the list grew as the movement grew.

Evangelicals today would be considered a subset of the Protestants, a subset that not only reject the traditions of the Catholic Church, both the Roman and the Eastern, but also those of the Anglican and Lutheran. Most Evangelicals feel Luther didn't go far enough in the Reformation, in limiting the role of church in the dispensation of grace.

They believe God's grace is solely administered through His Word. All the sacraments are memorial, a figurative depiction of the content of Scripture.

I think sola scriptura is an appropriate shibboleth to filter Evangelical from non Evangelical.

John Stott has been mentioned who was a globally influential Anglican vicar. His influence on the CoE continues to this day (see Note, final paragraph). He would have unequivocally argued the two "Protestant" and "evangelical" are exactly the same. This is most notably true within the Church of England (CoE).

The rationale is that John Store and colleagues, would hold/ do hold tightly to the 39 articles. This was written primarily by Archbishop Thomas Cranmer in 1553 on the foundation of the Church of England (CoE). This guy was the first archbishop of Canterbury and was later burnt at the stake for his Protestant beliefs. Thus, in summary the 39 articles is the founding document (the constitution) of the first officially/legally recognised English Protestant church.

So for example,

VI. Of the Sufficiency of the Holy Scriptures for Salvation.

XV. Of Christ alone without Sin.

XVIII. Of obtaining eternal Salvation only by the Name of Christ.

XXVIII. Of the Lord's Supper. (Transubstantiation is not permitted under XXVIII)

and so on ... There would be 100% doctrinal concordance with what John Stott believed and the 39 articles. There would be minor differences on the importance of certain ceremonies notably "homilies" XXXV. Of the Homilies.

Therefore, what John Stott and fellow-evangelical vicars (pastors) would believe and have stated is that the 39 articles is a resoundingly evangelical doctrine therefore the evangelicals were the original legally recognised English Protestants. I personally asked one of his colleagues, Jonathan Fletcher, after attending the talk where he laid out his theological principles on the history of the CoE. The question is more than simply academic within the CoE.

Legally recognised is an important term here, because all evangelicals would maintain there were plenty of evangelicals in England prior to the 39 Articles: free evangelicals would be particularly adamant about this. However, owning a bible in Great Britain would have been illegal in the early part of Henry VIII's rein. When Henry VIII was a Roman Catholic the bible was definitely banned and punishments e.g. for smugglers, were severe (the story goes one group were wrapped in firewood and told if they didn't top smuggling bibles next time they'd set fire to them).

Conclusion What I'm leading up to say is that Anglican evangelicals, such as John Stott (and me), maintain they are the original (legally recognised) protestants in the UK and point to the 39 articles as primary evidence. It very a strong argument, but it excludes the free-evangelical church (they are the best).

Whilst for most on this site (not all) this statement is not important, within the Church of England it is controversial because of its theological spectrum historically comprising Anglo-catholics, liberal theology and evangelical movement. I'm not sure if the charismatics align inside or outside the evangelicals. It's controversial because it gives precedence to evangelicals against other theological groups, and that is not permitted in the CoE it's about maintaining that balance to stabilise the church.

Note John Stott BTW was famous and decisive for maintaining the evangelical movement within the CoE against the free-evangelicals who wanted it out. The 39 articles would be have been foundational to that statement, "History has proved you wrong" he famously said to his opponents.

For purposes of this question, protestants can be divided up into three main camps:

1. Those that still closely align with or resemble Catholics, such as Anglicans, older Lutheran groups, and other highly-centralized and liturgical groups. This category tends to either vote exactly as the denomination suggests, or will discount religion in their voting patterns entirely. These denominations are currently more likely to be conservative, but have been liberal as well in the not-to-distant past. Because of the tendency to keep politics and religion separate and the relative small size (compared to Catholics), they don't get a lot of political attention.
2. Fundamentalist purist groups. These are "back to the bible" or "sola scriptura" groups that see themselves as separate from the rest of the culture. As a result of this separation, they have low voter turn-out and may not vote based on their religious views. These groups tend to be conservative and were very large 70 years ago. However, the fundamental purists are shrinking as a demographic, and again combined with their weaker voter solidarity don't get as much political attention any more.
3. Modern Evangelicals. These Christians are fundamentalists... just a more recent (and large, growing) adaption. Many that would have formerly been purist fundamentals are now aligned with this movement. Evangelicals are distinct from purists in that they also want to engage the larger culture. They have two goals in mind with this effort: make it easier to reach out (evangelize) Christ to others, and to make it easier and more socially acceptable to live a complete Christian lifestyle. The process of engaging the larger culture means Evangelicals are much more likely to turn out to vote, and when they vote it's also more likely to be based on their religious viewpoints. This has resulted in a lot of attention from political circles.

As a fairly new movement historically, Evangelicals will often have a progressive or liberal mindset rooted in compassion and are sensitive to social justice issues, but tend to vote conservative in spite of this because of a perceived anti-religion and sometimes openly-atheistic and antagonistic stance from other forces in the liberal camp, as well as the liberal position on certain issues (such as abortion) that is abhorrent to many Evangelicals.