By David DeKok
HARRISBURG, Pa. (Reuters) - A panel of federal judges on Friday will weigh Republicans' latest attempt to block new Pennsylvania district boundaries for voters in congressional elections that could boost Democrats' chances of winning control of Congress this year.
The state's Supreme Court issued the revised map last month after finding the old lines were drawn by the Republican-controlled legislature to marginalize Democratic voters in violation of the Pennsylvania constitution.
The new map increases Democrats' odds of winning some half-dozen congressional seats in Pennsylvania, according to political analysts. The party must flip 24 seats nationwide in November's mid-term elections to win the majority of the U.S. House of Representatives from Republicans.
Since the old boundaries were instituted prior to the 2012 mid-term elections, Republicans have held 13 of the state's 18 congressional seats despite the state's closely divided electorate.
Republicans have pursued two separate avenues of appeal, asking the U.S. Supreme Court to throw out the map while also filing a lawsuit in Harrisburg seeking an injunction to prevent the map from taking effect ahead of May's primary elections.
The U.S. Supreme Court, which rejected a similar appeal in February, has not yet ruled on the latest petition.
Several incumbent Republican congressmen are plaintiffs in the Harrisburg lawsuit, which will be heard by a three-judge panel as per federal law regarding electoral challenges.
State election officials have asked the court to throw out the lawsuit, arguing that the judges have no jurisdiction over a state court's decision.
In January, the Pennsylvania Supreme Court found the old map's bizarrely shaped districts – one of which earned the derisive nickname "Goofy Kicking Donald Duck" – were deliberately constructed to ensure Republicans would hold the advantage.
(Writing by Joseph Ax; Editing by Cynthia Osterman)