Wow, a third article on this topic in two days. Michael Gerson of the Washington Post reports:

In politics, some acts are so emblematic and potent that they cannot be
undone for decades -- as when Republican presidential candidate Barry Goldwater
voted against the Civil Rights Act of 1964. Goldwater was no racist;
his constitutional objections were sincere. Members of the Republican
Party actually voted for the Civil Rights Act in higher percentages
than Democrats. But all of this was overwhelmed by the symbolism of the
moment. In his autobiography,
Colin Powell says that after the Goldwater vote, he went to his car and affixed a Lyndon Johnson
bumper sticker, as did many other African Americans. Now Republicans
seem to be repeating history with Hispanic Americans. Some in the party
seem pleased. They should be terrified.

Thanks to Drew at Immigrants List for the link.