Yesterday we posted a quick round-up of the various voter-suppression schemes being pushed by Republicans in swing states around the country. And after looking at the list, one thing quickly becomes clear: most of the efforts have failed.

There's no one grand unifying theory for why that's true.

In some cases, the courts have rejected GOP efforts to make voting harder:

• In Indiana, for instance, a Superior Court judge declined to support a GOP bid to shut down early voting centers in Democratic-leaning cities in Lake County, and the state Supreme Court chose not to immediately intervene.

• In Wisconsin, a suit brought by Republican Attorney General J.B. Van Hollen -- which he later admitted had been requested by the Republican Party -- seeking to force the state election board to re-confirm all newly registered voters was thrown out by a county court.

• In Michigan, a federal appeals court today blocked the Republican secretary of state, Terri Lynn Land, from throwing 5,500 newly registered voters off the rolls because their registration cards were returned as undeliverable, after voting-rights groups sued.

In other states, Democratic state officials or voting-rights advocates have held the line:

• In Nevada, Secretary of State Ross Miller denied a request from the state GOP to require voters to cast provisional ballots if they fixed mistakes in their voting information at the polls.

• In Colorado, a bid by Republican Secretary of State Mike Coffman -- who himself is running for a seat in the U.S. House -- to purge 14,000 voters from the rolls was only partially successful. After voting-rights groups sued, a settlement was reached yesterday allowing the voters to cast provisional ballots. According to the Rocky Mountain News, those ballots would "be presumed to be valid unless state and county officials prove otherwise." A lawyer for the voting-rights groups called the deal "a win-win."

In still other places, it's been a combination of both factors:

• In Ohio -- perhaps the most high-profile example of voter-suppression this cycle -- the state GOP sued to force Secretary of State Jennifer Brunner to provide local election officials with the names of new voters whose registration information didn't match other government documents. Brunner resisted, arguing, it appears correctly, that the information would be used to challenge large numbers of voters and cause chaos at the polls. The U.S. Supreme Court ultimately sided with Brunner. (The Department of Justice deserves some of the credit here, too, for declining a request by the White House to intervene.)

And in some states, the Republicans appear to have done themselves in through the sheer chutzpah of their behavior, and the resulting outcry:

• In Montana, the state GOP announced plans to challenge 6000 voters in predominantly Democratic counties, based on discrepancies between in their listed addresses. But after even Republicans in the state denounced the ploy, the party backed off, and its executive director resigned.

• In New Mexico, the state party held a press conference at which it released the names, and some personal information, of ten voters, almost all Hispanic, that it said had voted fraudulently in a Democratic primary in June. It was later established that they were all legitimate voters. The U.S. Department of Justice is now investigating reports by TPMmuckraker and others that a lawyer attached to the party sent a private investigator to the homes of some of these voters to question them about their voting status -- potentially violating federal voting laws.

Of course, that's not to suggest that Republican suppression efforts haven't been successful anywhere. In Florida, for instance, Secretary of State Kurt Browning, a Republican, has instructed election officials to reject voter registration applications that do not pass a computer match test. Voting-rights groups say the system can disqualify voters based on nothing more than a missing middle initial on their voter form. They fear the move could disenfranchise tens of thousands of legitimate voters. (Though even in the Sunshine State, there's a bright spot. GOP governor Charlie Crist on Tuesday ordered extended hours for early voting centers, after long lines were reported in many parts of the state.)

Of course, the whole point of the voter-suppression game is to throw up as many gambits as possible, and hope that just a few succeed. And there's no way to measure the effect that even the unsuccessful ploys have in generating cynicism about the process itself, and thereby reducing turnout, to Republicans' advantage. So in a close election, it's still possible that voter suppression could make the difference -- as it may well have done in 2000.

But it's worth noting that -- thanks largely to Democratic control of the secretary of state's offices in some key states; the skepticism with which many courts have looked on efforts to put obstacles in the way of voting; and the role of voting-rights groups and the press in exposing the bankruptcy of Republican claims -- the nationwide GOP voter-suppression effort appears to have been far less successful than the party might have hoped.

Not that we expect them to drop the tactic any time soon.