"Blacks have had a potential force for years," said Sen. Howard M. Metzenbaum (D., Ohio). "The Bork nomination has transformed that into an effective force."
The implications of that clout could go far beyond the Bork nomination and help blur the distinctions between Southern Democrats and their Northern counterparts on other issues, including civil rights legislation and welfare reform.
"The Boll Weevils, for all intents and purposes, have disappeared in the House, and this may be a real signal as far as the Senate is concerned," said Sen. John McCain (R., Ariz.). "The lesson is, we may be seeing the end of the conservative Southern Democrat - or at least we may be seeing a generation of Southern Democrats much less conservative than their forefathers."
The importance of blacks to the Democratic Party in the South was vividly displayed in the 1986 congressional elections, which put Democrats back in control of the Senate.
At least four Democratic freshmen would not have won without black support, according to network polls of voters. Sens. Richard C. Shelby of Alabama, Wyche Fowler Jr. of Georgia, Terry Sanford of North Carolina and John B. Breaux of Louisiana captured well under half of the white vote, but emerged victorious on the strength of an overwhelming black vote.
Those numbers are not lost on other Southern Democrats, who have listened intently as civil rights groups have made no secret that Bork's defeat is their top legislative priority.
The lobbying campaign, led by the Leadership Conference on Civil Rights, began to bear fruit Thursday as three Southern Democrats - Sanford, David Pryor of Arkansas and J. Bennett Johnston of Louisiana - announced they would vote against Bork. On Friday, they were joined by a fourth, Sen. Lloyd Bentsen of Texas.
"If one wants to understand the dynamics of the Bork opposition, one should start with the Voting Rights Act of 1965. That's the central dynamic," said Fred Wertheimer, president of Common Cause and a leading anti-Bork lobbyist. The political empowerment of blacks, Wertheimer said flatly, "is where this story lies.
"Among the many factors affecting the opposition to Bork, the most important factor has been blacks and Southern Democrats."
Politicians cautioned, however, that it would be simplistic to view Bork's problems simply through the prism of race: Public opinion polls suggest that whites, too, are opposed to his elevation to the Supreme Court.
A survey of 6,452 people in 12 Southern states published Thursday by the Atlanta Constitution showed a 51 percent to 31 percent majority against Bork. Among blacks, the margin was 69 to 17 percent; among whites, it was 46 to 34 percent.
Several lawmakers have said they think a major problem for Bork is that both whites and blacks - particularly in the South - are concerned that his confirmation could reopen old civil rights battles on the court.
"Southern Democrats all lived through a very difficult period in American life that was particularly trying in the South," said Sen. George J. Mitchell (D., Maine), "and it's clear they don't want to go through that again. In that, I think they're speaking for the people of their region."
Legislators suggested that the Southern Democrats might be less inclined than before to worry about losing the support of white conservatives because many of the conservatives have switched from Democratic to Republican.
"We have seen a realignment of sorts," said Sen. Thad Cochran (R., Miss.). "Most conservatives have gone over to the Republican camp . . . so the influences in the South in the Democratic Party are much the same as they are in other parts of the country, with minorities, big labor, environmental activists becoming more important."
That influence may not be noticeable on many of the nuts-and-bolts issues before Congress that prompt little public interest. But on the "passionate issues, it will make a difference," predicted Sen. Bob Packwood (R., Ore.), who termed the impact of black opposition to Bork "immense."
Metzenbaum, likewise, sees far-reaching effects if the Bork nomination is defeated. "Once you realize you have an impact," he said, "you're more likely to exercise it."