The Trump campaign claimed it was filing suit to stop the vote count in Michigan, as it was staging a redux of the Brook Brothers riot of 2000 at a vote counting center in Detroit Wednesday. That's a direct attempt to try to intimidate poll workers. The campaign is going a different route to stop the vote counting in Pennsylvania, with margins in the state shrinking. With 1.1 million ballots still outstanding, the Trump campaign filed this suit, then immediately declared victory. That's both another attempt to intimidate, as well as telling the Supreme Court what they expect out of this.
To recap the Pennsylvania situation, the state Supreme Court ordered a three-day extension to allow counting of ballots clearly postmarked on or before Election Day or that had missing or illegible postmarks “unless a preponderance of the evidence demonstrates that it was mailed after Election Day.” The U.S. Supreme Court deadlocked, 4-4 leaving the Pennsylvania Supreme Court ruling to stand. Last week, the SCOTUS rejected a request from Pennsylvania Republicans to fast-track a rehearing, but three of the court's conservatives made it clear that they would welcome Republicans coming back if the vote is close enough, or Trump asks for it.
Knowing that the campaign was probably going to bring this case, Pennsylvania officials ordered counties to segregate those ballots received Wednesday through Friday, in order to make sure that the absentee, mailed-in, and early vote ballots would be walled off from the mischief of Team Trump.