HARRISBURG, Pa. (AP) — Republican congressmen who are suing to block Pennsylvania's court-ordered U.S. House district boundaries nonetheless began circulating petitions in those new districts Tuesday, as they hope and wait for a federal court to intervene.

Tuesday was the first day for candidates to collect signatures to get on May 15 primary ballots in the state's 18 districts, all of which were redrawn in a new map imposed by the state Supreme Court last week.

"We're all kind of waiting to see what will happen, but today is the first day to circulate and these guys are all circulating," said Mike Barley, a campaign consultant to six of the state's eight Republican congressmen who are running for re-election.

The state court's map overhauls a GOP-drawn congressional map that has helped produce a predominantly Republican delegation and was widely viewed as among the nation's most gerrymandered. The court's map also boosts Democrats' chances in several districts as the party aims to chip away at Republican control of the U.S. House in November's elections.

A campaign consultant to Rep. Scott Perry said there is still optimism that a federal court will block the districts imposed last week by the state Supreme Court, but that the court's map is still the only one before Perry.

"The way that he looks at this is, this is the battle that was brought to him, so this is where we're going to fight," consultant Mike DeVanney said.

The deadline to file signatures is March 20.

Primary fields are jam-packed, driven by a rush to fill six open seats, the most in Pennsylvania in four decades. More than 70 people, including 12 sitting U.S. House members, are either committed to running or say they are kicking the tires on a run. The redrawn districts are prompting some candidates to run in districts where they don't live, or to think about moving their home to a new district.

In the meantime, top state lawmakers are asking the U.S. Supreme Court to block the map, and reinstate the 6-year-old map drawn by Republicans who controlled the Legislature and governor's office in 2011. Perry and six other Republican congressman seeking re-election also are asking a federal court to block the state court's map.

Republicans redrew the districts in 2011 in an effort to get Republicans elected, creating bizarrely contorted boundaries that were very effective: Republicans won 13 of 18 congressional seats in three straight elections in a stretch when Democrats won 18 out of 24 statewide elections in Pennsylvania.

Last month, the Democratic majority on Pennsylvania's high court struck down the districts, saying the boundaries violate the elections clause of the state Constitution, which guarantees that elections "shall be free and equal."

After Democratic Gov. Tom Wolf and the Republican-controlled Legislature failed to agree on a redrawn map, the court imposed the new boundaries.