Interstate Crosscheck is a computerized system meant to identify fraudulent voters. While Crosscheck’s list of nearly 7 million names of “potential” double voters has yet to unearth, as of this writing, a single illegal vote this year, it did help Republican elections officials scrub voters from registries, enough, it appears, to have swung several important Senate and governor’s races in favor of the GOP.

There is good reason to believe that Crosscheck-related voter purges helped propel Republican candidates to slim victories in Senate races in Colorado and North Carolina, as well a tight gubernatorial race in Kansas.

Interstate Crosscheck is a computer system designed to capture the names of voters who have Illegally voted twice in the same election in two different states. The program is run by Kansas’ Republican Secretary of State Kris Kobach. Kobach’s office compares the complete voting rolls of participating states to tag “potential” double voters, those who have illegally voted twice in the same election in two states.

These names are then sent back to the state governments to inform an investigation of duplicate names on the voter rolls. While Kobach advertises Crosscheck as matching numerous identifiers, including the Social Security numbers and dates of birth of voters, a six-month investigation by Al Jazeera America revealed that Crosscheck rosters caught nothing more than matching first and last names. And voters remain on the suspect list even when middle names, Social Security numbers and suffixes (Jr., Sr.) don’t match. Yet all these people — the list contains nearly seven million names — are subject to losing their vote.

The program’s method of identifying and purging voters especially threaten the registrations of minority voters who are vulnerable because African-American, Asian-American and Hispanics are 67 percent more likely than white voters to share America’s most common names: Jackson, Washington, Lee, Rodriguez and so on.

See if your own name is on Crosscheck lists

It is no surprise that Republicans control most of the top election positions in Crosscheck’s 27 participating states. In all, Crosscheck tagged a breathtaking 6,951,484 voters for the possible removal from the voter rolls as “potential” duplicate voters.

Duplicate or double voting is a crime punishable by 2 to 10 years in prison. Yet, despite this supposed vote-fraud crime wave, not one suspect on Crosscheck lists was charged, although prosecutors would have access to any alleged fraudsters’ names and addresses.

The Crosscheck list purges could easily account for Republican victories in at least two Senate races. In North Carolina, the GOP’s Thom Tillis won over incumbent Sen. Kay Hagan by just 48,511 votes. Crosscheck tagged a breathtaking 589,393 North Carolinians as possible illegal double voters (though state elections officials cut that down to roughly 190,000).

In Colorado, Republican Cory Gardner was able to force out incumbent Senator Mark Udall in a race that had poll-watchers guessing all summer. The outcome might have been more predictable if Colorado had made public that 300,842 of the state’s voters were now subject to being purged from the voter rolls.

The Rocky Mountain State’s elections officials have a history of cleansing voter rolls without public explanation. Before the 2008 election, Colorado’s GOP Sec. of State Donetta Davidson began an unprecedented scrub of the electoral rolls, disenfranchising nearly one in six voters [PDF].

Not everyone on the Crosscheck lists loses their vote. But the purges are, nevertheless, huge. Just one state, Virginia, canceled the registrations of 41,637 voters last year, 13.5 percent of those on the list — and has since announced it will remove many more [PDF].