AUSTIN, Texas - Attorney General Eric H. Holder Jr. vowed Tuesday to fully enforce civil rights protections in next year's elections amid a flurry of activity by states to redraw political boundaries and impose requirements that could reduce voting by minorities who enthusiastically supported President Obama in 2008.

Giving his most expansive speech on civil rights since taking office, the nation's chief law enforcement officer declared that "we need election systems that are free from fraud, discrimination, and partisan influence - and that are more, not less, accessible to the citizens of this country."

He urged the country to "call on our political parties to resist the temptation to suppress certain votes in the hope of attaining electoral success."

"Instead, encourage and work with the parties to achieve this success by appealing to more voters," Holder said during an appearance in Austin.

The Justice Department is reviewing new requirements in Texas and South Carolina requiring voters to produce a photo ID before casting ballots. The department also is examining changes in Florida, which involve imposing financial penalties on third-party voter-registration organizations such as the League of Women Voters when they miss deadlines and shortening the number of days in early voting periods before elections.

Most of the changes have been promoted and approved by Republicans, who say they avert voter fraud. Democrats, citing studies suggesting there is little voter fraud, say the measures are aimed at reducing minority votes for their candidates.

Where a state cannot meet its legal burden in showing an absence of discriminatory impact, "we will object," Holder said at the Lyndon Baines Johnson Presidential Library and Museum. As president in 1965, Johnson was instrumental in passing the landmark law the Justice Department now uses to ensure voting rights in Texas, South Carolina, and all or parts of 14 other states.

Most of the 16 states are in the South, and all have a history of discrimination against blacks, American Indians, Asian Americans, Alaska Natives, or Hispanics. Besides Texas and South Carolina, Alabama, Kansas, Mississippi, Rhode Island, Tennessee, and Wisconsin have enacted more stringent voter ID laws this year.