The battle over voting rights in the November presidential election now swings to South Carolina, following the decision by the Pennsylvania courts on Tuesday to delay implementation of a voter ID requirement in that state.

All eyes are now on the legal tussle between the department of justice and South Carolina, where probably the last voter ID law will be decided before election day on 6 November.

Last year South Carolina became one of at least 34 states to introduce strict laws that require voters to present photo identification at polling stations – one of a swathe of measures attacking voting rights that swept across the US this election cycle.

South Carolina's law was blocked, however, by the Obama administration last June.

The department of justice wielded its powers under section 5 of the 1965 voting rights act – a safeguard introduced after desegregation in the deep south to prevent designated areas from changing voting procedures without federal government approval in advance.

The blocking power was designed consciously to counter the old Jim Crow laws of the south, where African Americans were routinely denied the right to vote on spurious technical grounds.

The justice department's final decision over the South Carolina's voter ID law is now pending and could be announced as early as this week. It is also possible, though, that a final ruling will be postponed until after the presidential election.

The assault on voting rights has been one of the epic themes of the 2012 election cycle, with states moving on an unprecedented scale to erect barriers to easy access to the polling booth. A tally by the Brennan Center for Justice in New York itemised at least 180 restrictive bills in 41 states

over the past two years, of which 15 laws were actually passed in 19 states.

The laws included a range of different threats to voting, of which the imposition of a requirement for photo ID cards was just the most common. Other laws required proof of citizenship at the polling station; at least 16 states introduced bills that would make it harder to register to vote; and at least nine have tried to end early voting.

But if 2012 has been the presidential election that saw a widespread attack on voting rights, it has also been a year that has seen a dramatic counter-offensive that has effectively neutralised most of the most egregious new laws. In no fewer than in 14 states have there been moves to repeal, postpone or judicially overturn the provisions.

In addition to South Carolina, the justice department used section 5 to block voter ID laws in Texas and Florida, the governors of six states wielded their vetoes, and there have been court cases settled or pending in seven states.

The intervention of judges around the country to hold back some of the harsher legislation has been notable aspect of the 2012 battle over voting rights. Lawrence Norden of the Brennan Center said that a common feature of judges' rulings against the voter ID laws had been "a recognition that a lot of this stuff has been politically motivated. It was not about improving the voting system, but about gaming the system."

Some of the judges made the thought that political skulduggery explicit in their

deliberations. A federal judge, Robert Hinkle, was scathing about a provision introduced by Florida that would penalise charities if they lodged new voter registrations with election officials more than 48 hours after they were completed.

Striking down the provision, Hinkle said: "If the goal is to discourage voter-registration drives and thus also to make it harder for new voters to register, the 48-hour deadline may succeed. But if the goal is to further the state's legitimate interests without unduly burdening the rights of voters and voter registration organizations, 48 hours is a bad choice."

When the Pennsylvania supreme court heard legal argument on the state's new voter ID law last month, one justice, Seamus McCaffery, wondered aloud why the legislature was in such a rush to implement the act in November. "Could there be politics, maybe?" he asked.

Planning for beyond November

While it seems the bulk of the threat to voter rights has been neutralised in

this presidential election cycle by the combination of judicial, gubernatorial

and electoral push-backs, in the longer term the danger is by no means

over. As the NAACP is pointing out this week with the launch of a new

campaign called Silenced: Citizens Without a Vote, there are almost 6 million citizens in the US who have been stripped of their votes as a result of having been convicted of a felony. That is equivalent to one out of every 40 American adults.

Four states – Florida, Virginia, Kentucky and Iowa – effectively permanently disenfranchise anyone with a felony conviction, even after they have fully served their sentence. Benjamin Jealous, NAACP's president, called the laws outrageous: "This is a country in which we believe voting is a right, in which all people should have a second chance," he told MSNBC.

Elisabeth MacNamara, president of the League of Women Voters which has an active voter registration programme in several states, said there was still the danger of considerable confusion among the electorate before November. "We are having to scramble to make up for months of lost time because of these laws," she said.

Beyond November, the voting rights issue is likely to raise its head again as legislatures who have had their efforts foiled move to reintroduce the offending legislation. Some rulings, including Tuesday's court judgment in Pennsylvania, have only delayed rather than eradicated the new voter ID laws which are likely to come into effect next year in the absence of any further opposition.

In addition, several places, including Texas and Arizona and parts of Alabama and North Carolina, are gearing themselves up to challenging section 5 itself. They argue that they should no longer be subjected to federal restrictions, though many voting rights experts remain suspicious of their motivations.

"Unfortunately, I think we will continue to see these battles well after the election," Norden said. "The fight is definitely still on-going."