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A three-judge federal appeals panel on Friday dismissed a lawsuit filed by Democrats in the state Senate who had hoped to derail a new round of Republican-led congressional redistricting in Texas.

The Democrats argued that Senate rule changes by Republicans to further the redistricting effort violated federal law. The judges, who listened to two hours of arguments Thursday in Laredo, dismissed those claims.

The ruling represented another setback for Democrats who have been fighting for several months to thwart GOP efforts to redraw the state's congressional map. They say it would hurt minority representation in Congress.

Democrats have a 17-15 majority in the current congressional delegation in Washington, and the GOP is pushing plans that would give Republicans as many as 21 seats.

"We said before the ruling that whatever happened today was just one more step in a long and challenging process and there are many unresolved issues that lie ahead," said Democratic state Sen. Judith Zaffirini (search).

Republicans said the decision reinforced their belief that the Legislature, not the courts, should decide redistricting.

"The Democrats have exhausted all their legal options and now it's time to get back to work," said Mark Miner, a spokesman for Republican Lt. Gov. David Dewhurst, who presides over the Senate.

Eleven Democratic senators fled to New Mexico on July 28, shortly before Republican Gov. Rick Perry (search) called lawmakers back for a second special legislative session to deal with redistricting. The senators went across the state line so Texas law officers could not arrest them and force them back to the Capitol.

The boycott brought the Senate to a standstill because not enough senators in the 31-member chamber were present to make a quorum, killing the redistricting effort.

But after the session ended, one of the Democrats, Sen. John Whitmire (search) of Houston, defected from the group and returned to Texas, saying he would attend the next special session — set to start Monday.

The remaining Democrats returned to Texas this week to attend the hearing on their lawsuit.

In court Thursday, judges closely questioned the Democrats' attorney, Paul Smith, who argued that dropping a Senate rule requiring two-thirds of the 31 members to agree to debate a bill violated the federal Voting Rights Act (search), enacted to protect minority voters.

The court withheld a decision on a complaint of threats to arrest Democrats and require them to pay fees for their failure to appear at the second special session.