Working ballot by ballot, county by county, the Republican Party is attempting to alter voting laws in the biggest and most important swing states in the country in hopes of carving out a sweeping electoral advantage for years to come.

Changes already on the books or in bills before state legislatures would make voting harder, create longer lines, and threaten to disenfranchise millions of voters from Ohio to Florida, Pennsylvania to Wisconsin, Georgia to Arizona and Texas.

Efforts underway include moving election days, ending early voting and forcing strict new voter ID laws. The results could significantly cut voter turnout in states where, historically, low participation has benefited Republicans.

In the 10 months since President Obama created a bipartisan panel to address voting difficulties, 90 restrictive voting bills have been introduced in 33 states. So far, nine have become law, according to a recent comprehensive roundup by the Brennan Center for Justice – but others are moving quickly through statehouses.

“We are continuing to see laws that appear to be aimed at making it more difficult to vote—for no good reason,” Daniel Tokaji, an election law expert at Ohio State University, said in an interview.

This is not what election experts predicted after 2012, when the GOP’s voter suppression attempts backfired. Some laws were blocked by the courts. Still, restrictive legislation did not halt record turnout by black and Latino voters. Non-white voters made up a larger-than-ever share of the electorate last fall, and gave eight in 10 votes to President Obama.

In next year’s midterm elections, control of the Senate could well hinge on minority turnout in a few key states.

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After the GOP’s 2012 loss, some prominent Republicans urged their party to woo, not alienate, the growing minority electorate.

In May, Ohio’s Republican secretary of state, Jon Husted—no voting-rights crusader—slammed the “hyperbole” over voter fraud, acknowledging that it’s not widespread. Republican officials in Arizona and Colorado pointed to an epidemic of illegal immigrant voting, but recent reviews suggested the phenomenon is nearly non-existent in both states. And last month, Judge Richard Posner, who sits on the U.S. Court of Appeals for the Seventh Circuit, said he’d erred when he voted in 2007 to uphold an Indiana voter ID law in a crucial case that smoothed the legal path for similar measures to be enacted. In a new book, Posner wrote that such laws are “now widely regarded as a means of voter suppression,” something that hadn’t been clear because the impact of the laws hadn’t yet been felt.

The GOP campaign has been three-pronged: muscling tough new laws through state Republican-controlled legislatures; using state-level executive power to change voting rules; and fighting in the courts to defend harsh existing measures. The changes are designed to affect local, state, and national races in favor of Republican candidates at every level.

In the south, the effort has been aided by Shelby County v. Holder, the Supreme Court decision in June that weakened the Voting Rights Act. But it’s also going strong in states that were unaffected by the ruling.

One such place the perennial swing state of Ohio, the most important state in the last three presidential elections. As msnbc reported Tuesday, state Republicans are looking to rush through laws that would cut early and absentee voting, end same-day voter registration, and even reduce the number of voting machines on hand.

Together, the laws are a blueprint for longer lines on Election Day. Voting-rights advocates fear a repeat of 2004, when winding lines in predominantly urban areas of the state kept some voters waiting up to 10 hours. Many gave up in frustration.

In Wisconsin, another key swing state, the GOP is readying a bid to eliminate weekend voting, and give populous counties less flexibility to keep early voting offices open late in response to a flood of voters. The bill would also lead to a reduction in early-voting hours for the state’s two biggest cities, Milwaukee and Madison, which happen to be Wisconsin’s most important Democratic strongholds. The Wisconsin state Senate sponsors of the measure has said early voting in those cities is “out of control” and should be “reined in.”

At the same time, the state’s Republican administration—led by Gov. Scott Walker, a rising GOP star and potential 2016 presidential candidate—is fighting in court to enact a strict voter ID law that was passed in 2011 and blocked by a judge last year.

Pennsylvania, with its 20 electoral votes, has gone to Democrats for the last six cycles, but a Republican candidate would get a huge boost from making it more difficult for minorities to vote. The state is currently defending its own voter ID law in court after a judge barred it from going into effect before last fall’s election. One Republican leader in the legislature bragged last year that the law would have made it possible for Republican presidential candidate Mitt Romney to win Pennsylvania. The state’s numbers show around 750,000 voters—disproportionately black and Hispanic—lack the required ID.

Arizona and Kansas have gotten creative in their efforts. In June, the Supreme Court rejected an Arizona law requiring proof of citizenship to register to vote. In response, the two states argued that the ruling applies only to federal elections. The states are now looking to make voters register twice—once for federal elections, without requiring proof of citizenship, and once for state and local races, with the citizenship requirement.

The scheme would create two classes of voters—those approved for voting in all contests, and those restricted to federal elections. The last state to enact a dual-registration system was Mississippi in the 1890s—you can guess for which purpose.

In North Carolina, an increasingly purple state, but one where Republicans have been in full control since the start of the year, the GOP passed what is perhaps the most regressive voting law in recent memory. Among other provisions, the measure cut early voting, ended same-day voter registration, ended a popular pre-registration program for high-school students, and instituted a strict photo ID requirement.

A local GOP official resigned last month after telling The Daily Show, “If it hurts a bunch of lazy blacks that wants the government to give them everything, so be it.”

The U.S. Justice Department is challenging the law, arguing that it disproportionately impacts minorities.

Texas, the top long-term target for Democrats thanks to a skyrocketing minority population, is continuing to fight in court for its 2011 voter ID law, which Attorney General Eric Holder has called a “poll tax”. A federal court ruled last year that the law discriminated against blacks and Hispanics, but it was reinstated after the Supreme Court’s ruling on parts of the Voting Rights Act. The state has argued that the measure passes muster because it targets Democrats, not minorities.

In this month’s election, the law nearly disenfranchised a 90-year-old former Speaker of the U.S. House of Representatives. But its real impact is likely to come next year, when a high-profile governor’s race could draw a large number of new voters to the polls.

Photo ID laws in Virginia—which twice went for Barack Obama—South Carolina, Arkansas, and Alabama are set to go into effect next year or soon after, all given crucial momentum by the Supreme Court’s ruling.

Florida—whose dysfunctional election system made headlines last November—is reviving a flawed purge of the voter rolls, which last year nearly disenfranchised a 91-year-old World War II vet before a court stopped it. Between the long voting lines and the purge, a repeat of the state’s infamous 2000 election fiasco can’t be ruled out.

A separate slew of changes to local election rules—in Texas, Georgia, and Arizona, among other places—were set in motion by the Shelby ruling and threaten to reduce black and Hispanic political power at the ground level.

Of course, Democrats and voting-rights advocates won’t take these changes lying down. As well as ground-level organizing efforts, they’ve already filed suit against the most restrictive laws, and over the next year they’re likely to file several more. Last fall, the courts acted quickly to block several of the worst changes before Election Day.

But there’s no guarantee that will happen again. And if it doesn’t, some of these measures could stay in effect through the next election cycle or two, if not beyond. By then, they’ll already have served their purpose.