The response was a ballot initiative to reverse the decision, and to amend the state constitution so that the protections and rights were rolled back. This passed convincingly at the ballot box.
There was a legal challenge. The state refused to defend the amendment, to the ire of its supporters. The courts stepped in, and ultimately found that that the amendment was unconstitutional. Despite the support of the majority of voters, it was declared invalid.
Proposition 8? No.
I'm talking Proposition 14, which was passed in 1964 with a whopping 65% majority, and ultimately declared unconstitutional by the US Supreme Court in 1967.
The story: in 1963, the California legislature passed the Rumford Fair Housing Act that stated property owners could not refuse to rent or sell property to anyone because of ethnicity. It also included religion, sex, marital and family status, and physical handicap. This was considered an important landmark for civil rights.
In 1964, Proposition 14 (sponsored by real estate and Republican groups) stated that property owners could indeed discriminate. As I said, it passed convincingly.
When it was challenged in court, the state declined to defend Proposition 14, because Gov Pat Brown (Jerry Brown's father) considered it unconstitutional. The California Supreme Court found that Prop 14 violated equal protection clause of the fourteenth amendment.
The Supreme Court of the US agreed. In Reitman v. Mulkey (1967), SCOTUS invalidated Prop 14 by a 5-4 decision. From the decision, they pointed out the real consequences of Prop 14:
The right to discriminate, including the right to discriminate on racial grounds, was now embodied in the State's basic charter, immune from legislative, executive, or judicial regulation at any level of the state government. Those practicing racial discriminations need no longer rely solely on their personal choice. They could now invoke express constitutional authority, free from censure or interference of any kind from official sources. All individuals, partnerships, corporations and other legal entities, as well as their agents and representatives, could now discriminateAs Wikipedia tells us, "Reitman established a significant precedent because it held that state assistance or encouragement of private discrimination violated the equal protection guarantee of the Fourteenth Amendment. As of 2013, this precedent remains good law."
You might want to pass this along to the bloviating anti-equality die-hards, who continue to advocate for the right to do just that.