What it would take for a Democrat to win Alabama

Moore has earned a smaller vote share than all but one recent presidential, gubernatorial or Senate candidate. (In 2002, Republican Bob Riley won the governorship by a 0.8 percent margin — and in 2004, Sen. Richard Shelby won by 35 points.) Moore also ran for governor in 2010 and finished fourth, with 19 percent of the vote in the Republican primary.

All this is to say — in Alabama, Roy Moore is not a popular Republican. Popular enough to win but unpopular enough to lose a significant number of his party’s votes in the process. That pattern, in addition to the allegations against him, mean that Democrat Doug Jones may have an opening to win. And where Moore underperforms the most — the northeast and areas near big cities — Jones may have the most potential.

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Alabama’s geography — and politics — are sharply divided by race.

Alabama’s black population — 27 percent of the state overall — is concentrated in cities and the Black Belt in central Alabama. These areas vote strongly Democratic, while whiter parts of the state are strongly Republican.

“It’s pivotal that [Jones] has large African American turnout,” said Steve Flowers, an Alabama political columnist. Birmingham, the state’s most populous city, “is where this will be won and lost.”

Whether Jones can get voters in predominantly black areas to turn out for a special election — which tend to have low participation — is an open question.

Republicans historically get most of their votes from the white, rural parts of the state, and low turnout there is possible. “I expect a potential dropoff in the northern part of the state — the white, evangelical counties,” said Gerald Webster, a professor at the University of Wyoming who has studied Alabama political geography. “Turmoil will suppress it.”

Other than staying home, some Republican voters may even cross over to vote for Jones. Flowers says he expects it in the suburbs of Birmingham, where white young professionals “are more sophisticated and more urbane” than those in rural areas. “They’re embarrassed by Moore. … They’re going to vote for Doug Jones if they vote at all.”