The U.S. Supreme Court on Monday rejected a request from Pennsylvania Republicans to block a new congressional map drawn by the state Supreme Court from taking effect, handing Democrats a major victory as the new map gives them an edge.

Republican legislative leaders had asked Justice Samuel Alito last month to put the order from the state Supreme Court on hold. The high court announced Monday it denied that request. There were no noted dissents.

The high court’s refusal to stop the new map from taking effect means the district lines drawn by the Pennsylvania Supreme Court last month will remain in place for the upcoming primary and general elections.

Under the initial map drawn by the GOP-led General Assembly in 2011, Republicans held 13 of 18 seats. They lost one of those seats last week in the special election won by Democrat Conor Lamb.

But the new court-drawn map is more favorable to Democrats.

The Pennsylvania Supreme Court invalidated the 2011 map as an unconstitutional partisan gerrymander and ordered state Republican legislative leaders to draw new congressional boundaries.

Republicans did so, but their proposed map was rejected by Gov. Tom Wolf, a Democrat, last month.

The Pennsylvania Supreme Court then stepped in and drew new district lines.

Republican state legislators challenged the court-drawn congressional map and said the state’s highest court had usurped the legislature’s authority to draw district lines.

Two state Pennsylvania GOP leaders and eight Pennsylvania congressional Republicans challenged the court-drawn boundaries in federal court, and GOP lawmakers also asked the U.S. Supreme Court to step in.

But their efforts failed, as the federal district court dismissed the case from Pennsylvania Republicans earlier Monday.

