Key lawmakers vowed Wednesday to ensure the full Voting Rights Act is restored to full strength, following the Supreme Court’s June decision to strike down part of the law.

Rep. Jim Sensenbrenner of Wisconsin, the GOP negotiator of the law’s most recent reauthorization, testified before the Senate Judiciary Committee that the high court decision “severely weakened the protections both Republicans and Democrats fought hard to preserve” and that he already is working on a response to deal with the new gaps in the law.

“The Voting Rights Act is the most successful of all civil rights acts in actually limiting discrimination. We cannot afford to lose it now,” the former House Judiciary chairman said. “I’m working to pass a constitutional response to the Shelby v. Holder decision.”

In front of his Senate colleagues, however, Sensenbrenner conceded the challenges he faces in the GOP-controlled House. When he pushed to reauthorize the legislation in 2006, it was in part because he feared that when he surrendered his gavel to caucus-imposed term limits, his successor would not work to re-up the law.

“Sometimes the difference between [the House] and the Senate is the difference between here and the moon,” Sensenbrenner said.

Civil rights icon Rep. John Lewis, D-Ga., also testified before the committee, telling senators that the Supreme Court decision left him heartbroken but resolute in trying to restore the formula that empowers the “preclearance” clause of the law. That provision gave the Department of Justice the right to block moves from states and municipalities viewed as discriminatory toward voters.

“The right to vote is precious; it is almost sacred.  It is the most powerful non-violent tool we have,” Lewis said. “It is my belief that we need the Voting Rights Act more than ever.”

Lewis stressed that it was Congress’ duty to “restore the soul” of the law because states are already imposing new statutes to disenfranchise voters. But as his GOP colleague hinted, that will be tough to do with divided government, even though previous reauthorizations have been overwhelmingly bipartisan.

Senate Judiciary Chairman Patrick J. Leahy, D-Vt., said he held the hearing on the partially collapsed law Wednesday because he wanted the conversation to take place before the August recess, when lawmakers and constituents have the most opportunity to interact and push for a rewrite of the now-unconstitutional preclearance formula. Though the decision was made to hold Wednesday’s session on the VRA in the full committee, Leahy suggested that Sen. Richard J. Durbin’s Subcommittee on the Constitution would be integral in the Senate’s efforts to rework the law.