Democrats’ spirits are high as they view a presidential election that could put the Barack Obama-Joe Biden ticket in the victory column in November. However, after a stirring national convention in Denver and apparent moves toward more unity for the Democrats, there still are countless other factors to contend with if McCain is to be beaten.

One aspect that has been periodically cited but which continues to linger in the background as a potential hindrance is “The Tom Bradley Effect,” which describes the fate of a 20-year mayor of Los Angeles who sought the California governor’s seat in 1982. Rightly or wrongly, it involves racial overtones, an issue no one can be sure won’t affect Obama’s campaign this fall.

Bradley was a son of a Texas sharecropper and the grandson of former slaves. He fought and overcame countless obstacles. When the family moved to Arizona to pick cotton, Bradley helped. In 1924 the family moved to Los Angeles where the father was a railroad porter and his mother worked as a maid.

Tom Bradley, eventually an outstanding baseball and football player, kept growing and entered the field of politics in the 1950s. He became the 38th mayor of Los Angeles and served five terms in that post, from 1973 to 1993. He was the first African-American mayor of Los Angeles and only the second black mayor of a major American city.

In 1982, the well-respected Bradley decided to run for governor. Several polls indicated just before the election that Bradley had a lead of 8 to 10 percentage points over Republican George Deukmejian. As the voting sites closed, early evidence was that Bradley was winning.

Yet racial dynamics that existed then, as they may now, were blamed for what turned in to a narrow loss for Bradley. He fell short by about 100,000 votes, about 1.2 percent of the 7.5 million votes cast.

So arose the term “The Bradley Effect.” It describes a tendency of image-conscious white voters to tell interviewers or pollsters they are undecided or are likely to vote for a black candidate but then actually vote for the opponent.

What happened to the Los Angeles mayor in 1982 is something that the Democrats and the Obama-Biden duo have to keep in mind this year. Polls indicate that millions of Americans say they will vote for the first black presidential candidate in our history, but are polls flawed by the kind of backtracking that occurred in the 1982 race?

Barack Obama is the same kind of charismatic and handsome candidate that Bradley was in California. Have Americans responding to polls become more honest and direct than those in California in 1982? Many think there is evidence of that.

If Obama and McCain reach election day relatively even in the polls, will racial dynamics close the gap in favor of the Republican?

It is an issue about which many Democratic leaders are concerned.