A conservative backlash to the massive street demonstrations over immigration is aggravating Republican leaders' carefully orchestrated plans to renew the landmark Voting Rights Act before the fall elections.

After Latinos came out in greater force than they have in decades to protest a House-passed immigration bill, conservatives persuaded Republican leaders not to force a vote last month to extend the law that requires bilingual ballots in precincts with large non-English-speaking populations.

They joined with a group of southern Republicans who object to extending the law's requirement that nine states have federal oversight decades after they quit hindering blacks' access to voting booths through Jim Crow laws.

Now back from their July 4 recess, House leaders want to try again to extend the 1965 law that eliminated anti-black voting practices and, through later amendments, practices that also discriminated against other minority groups. They planned a possible vote for Thursday, but prospects of it occurring were dim.

"I want to finish this bill this week," House Majority Leader John Boehner, R-Ohio, said Tuesday. "But to tell you honestly that everything has been resolved and everyone is happy would not be the truth."

Immigration and civil rights groups and lawmakers who support them are mobilized for a fight over what they see as the latest in a long history of attempts to undercut burgeoning political influence of racial minorities.

"The historical record suggests that when minority communities are in a position to exercise political power, efforts to limit that exercise of power follow," said Debo Adegbile, associate director of litigation at the NAACP Legal Defense and Educational Fund.

Since 1975, the Voting Rights Act has required ballots and other election assistance in languages other than English in jurisdictions where at least 5 percent of voting-age citizens are not proficient in English and literacy rates are below the national average.

As part of its immigration debate earlier this year, the Senate voted to make English the official national language. That effort has flowed into Voting Rights Act deliberations, even though the law applies only to American citizens.

Opponents say renewing the requirement to provide election assistance in other languages discourages people from learning English and is unconstitutional.

Linda Chavez, president of One Nation Indivisible, a conservative think tank that promotes assimilation of immigrants, said language assistance was made part of the law three decades ago as a "power play" by civil rights groups who wanted Hispanics to have a piece of the action.

"The idea that this is some racist plot over the right to vote is just ludicrous," Chavez said, contending that help for non-English-speaking voters was intended to be temporary in the first place.

Marc Morial, president and CEO of the National Urban League, said he is puzzled that after 30 years, with no vociferous outcry from communities, there is suddenly an effort to strip out the act's language requirements.

"It smacks of an effort to impose a 21st-century literacy test," Morial said.

Some Republicans also have pushed for changes that require nine states — Alabama, Alaska, Arizona, Georgia, Louisiana, Mississippi, South Carolina, Texas and Virginia — to get "pre-clearance" from the Justice Department before making any voting or election changes.

Civil rights activists see a recurring pattern. The post-Civil War era of Reconstruction brought for newly freed blacks a chance to vote, own land, get an education and participate in the political process. But many states passed Jim Crow laws segregating public places and denying ballots to blacks through literacy tests and poll taxes until passage of the 1965 law.

What followed its enactment were new efforts to weaken or dilute the effect of minority voters through redistricting and new voter registration rules, said the NAACP legal defense fund's Adegbile. "This is well-trodden ground," he said.

Just two weeks ago, the Supreme Court struck down a 2003 redrawing of a Texas congressional district by Republican designers who carved out 100,000 Hispanic voters and replaced them with 100,000 white voters to ensure the re-election of Rep. Henry Bonilla, R-Texas.

The court said the move trampled on Hispanics' voting rights as they were becoming a political force in the district.