The Justice Department may attempt to block a slew of new state laws changing requirements to vote, that's the warning being issued tonight in speech by Attorney General Eric Holder in Texas. If- the department decides to challenge laws in more than a dozen states, including some that are now requiring photo identification in order to vote-it could lead to legal showdowns over the ballot box  in a variety of states in the middle of a white hot election year. And the potential showdown is likely to stoke the animosity between Attorney General Eric Holder and Republican members of Congress who already been battling over a controversial ATF operation.

According to Holder, the key question is whether the new laws have a discriminatory or disproportionate impact on minorities and the elderly. In referencing the dozen or so states that have recently changed voting guidelines, Holder specifically singled out Texas, South Carolina and Florida as being under review. Texas and South Carolina have seen changes involving "photo identification requirements"  and  in Florida there have been changes to early voting procedures.

" Although I cannot go into detail about the ongoing review of these and other state-law changes, I can assure you that it will be thorough - and fair, " Holder will say.  "We will examine the facts, and we will apply the law.  If a state passes a new voting law and meets its burden of showing that the law is not discriminatory, we will follow the law and approve the change.  And where a state can't meet this burden, we will object as part of our obligation under Section 5 of the Voting Rights Act. "