JACKSON, Miss. — After black voters helped Senator Thad Cochran of Mississippi survive an intense Republican primary runoff against an insurgent conservative challenger, some civil rights leaders in the South want him to repay the favor.
They say Cochran should lead the charge in the Senate to renew a key section of the Voting Rights Act struck down last year by the Supreme Court’s conservative majority.
‘‘But for the Voting Rights Act, those African-Americans who turned out to the polls . . . to support his reelection would not have had the opportunity to do so,’’ Mississippi NAACP President Derrick Johnson said.
Cochran angered some conservatives with his unabashed appeal to Democrats in the June 24 runoff election against state Senator Chris McDaniel, who eked out a win with the support of Tea Party groups in the state’s primary but did not win the outright majority required to avoid a runoff against the six-term incumbent.
Black Mississippians, who AP exit polls have indicated vote overwhelmingly Democratic otherwise, have backed Cochran in general elections but have never been such a key voting bloc in a contested GOP contest.
He must now ponder how to respond to that unusual primary coalition while mending fissures inside the state GOP, which is mostly supported by voters who are white.
That task is complicated by requests such as those made by Johnson, as well as a potential legal challenge from McDaniel.
He and his supporters contend — so far without presenting any definitive evidence — that Cochran won because ‘‘liberal Democrats’’ voted in the June 3 Democratic primary and then in the Republican runoff three weeks later, violating the state’s ban on what is called crossover voting.
McDaniel said Friday on CNN that his campaign found at least 5,000 irregularities in voting, and he will mount a legal challenge ‘‘any day now.’’
It was just one more twist in an election that affirms politics in Mississippi and surrounding Southern states is sometimes still all about race, even a half century after President Lyndon Johnson signed the Civil Rights Act of 1964 and the Voting Rights Act of 1965.
‘‘One has to be careful what we ask the senator to do,’’ said Delegate Eleanor Holmes Norton, the District of Columbia’s envoy to Congress who worked in Mississippi during the civil rights movement as part of the Student Nonviolent Coordinating Committee.
‘‘Everyone expects to get votes from both sides, and he’s been under attack from that,’’ she said. ‘‘I wouldn’t expect him to immediately stand up and make this his fight. His first task is to get himself back to the Senate.’’
Cochran was among the Republicans who generally celebrated the Supreme Court’s decision a year ago to remove from the Voting Rights Act a requirement that governments in 15 states with a history of discrimination seek and win federal approval before making changes to their election laws and procedures — from polling hours to precinct borders.
‘‘The court’s finding reflects well on the progress states like Mississippi have made,’’ Cochran said after the court ruled, adding ‘‘our state can . . . ensure that our democratic processes are open and fair for all without being subject to excessive scrutiny.’’
Many voting rights advocates, particularly the NAACP and other minority advocacy groups, maintain that federal oversight is still needed. An effort is underway to address the court’s concerns that the law was based on old data by restoring the ‘‘preclearance’’ requirement to four states with a recent history of voting discrimination — Georgia, Louisiana, Texas, and Mississippi.
That legislation is caught in the same partisan gridlock that has stalled action on most issues in the current Congress, and Holmes said it is accepted on Capitol Hill that there will be no votes before November’s midterm election.