The first legal test for Pennsylvania's tough new voter identification law is arriving.

A state Commonwealth Court judge will begin a hearing Wednesday on whether to block the law from taking effect in this year's election while the court considers a challenge to its constitutionality.

The hearing could last a week.

The law is the subject of a furious debate over voting rights as Pennsylvania is poised to play a key role in deciding the presidential contest in the Nov. 6 election.

Republicans say it's necessary to prevent fraud. But Democrats say it's an election-year scheme to steal the White House and contend that there's no track record of fraud that it would prevent.

Republican Gov. Tom Corbett signed the law in March without a single Democratic lawmaker supporting it.