Evangelicals reached the political mainstream and allied with Republicans by the 1950s

Evidence

But by the 1950s, the baby boom was in full swing and the “traditional” family appeared to be flourishing. … In the 1950s, too, Americans of all sorts were reinvesting in religion. Churches were springing up in new suburban neighborhoods across the country, and Sunday schools were bursting at the seams. Cold War politics also united Americans across party lines. To their delight, evangelicals found themselves securely within the political and cultural mainstream. … By the end of the decade, evangelicals had become active participants in national politics and had secured access to the highest levels of power. And they had come to see a Republican president as an ally in their cause. — Kristin Kobes Du Mez, Jesus and John Wayne, 85

Categorization

• QUESTION: Which Republican president? Eisenhower — worth noting that the evangelical-Republican alliance predates the Religious Right by two decades.
• XREF: connects to: American evangelicalism was politically reformist long before it aligned with the right — Randall Balmer, Bad Faith: Race and the Rise of the…, 41; Billy Graham fused Christian identity with American patriotism as early as the 1950s — Andrew L. Whitehead, American Idolatry, 237