Mitch McConnell. Chip Somodevilla/Getty Images Senate Majority Leader Mitch McConnell has had to stave off fights with influential outside conservative groups that are frustrated with the Senate's slow pace of confirmation for President Donald Trump's judicial nominations, Politico reported Monday.

One such group, the Judicial Crisis Network, planned to launch a $250,000 ad campaign in Washington, DC, on Tuesday that called on McConnell to either change Senate rules to help push through Trump's judges, or keep the Senate in session until Democrats relent in their efforts to slow the process, the outlet reported.

"The campaign, including the advertising, is in a holding pattern for now because Leader McConnell's office has reached out and wants to have discussions about how best to proceed in the coming months in order to avoid the kind of judicial confirmations bottleneck that the groups are concerned about," a Judicial Crisis Network spokesperson said in a statement to Business Insider.

Politico reported that a second organization, the Conservative Action Project, is pushing McConnell to end the practice of having the Senate's weekend start Thursday afternoon so that more time can be taken to focus on confirming nominees.

The push comes as Trump recently hit 65 combined nominations between appeals courts, district courts, the US Tax Court, and the US Court of Federal Claims. There are currently roughly 140 vacancies on the federal bench, providing Trump with the opportunity to cement a lasting legacy on the courts.

Trump has nominated judges at a breakneck pace, far outpacing his predecessors. But relatively few of his choices have been confirmed.

Trump's most recent wave of nominations came as the Senate is battling over what to do with the "blue slip" practice, which has come under fire from some Republicans.

The blue slip is a tradition in which US senators can give or withhold their blessing for a judicial nominee from their state. The process gives the party that does not control the White House leverage over the president's nominations, and some Democrats have used that power to deny Trump's nominees from moving forward in the Senate Judiciary Committee. That, in turn, makes it easier for Trump to advance nominees in states that do not have any Democratic Senate representation.

With Democrats now having the ability to — in many states — prevent Trump's judicial nominees from advancing, McConnell told The New York Times recently that he thought the blue-slip practice should be scrapped for circuit-court nominations. That sparked backlash from Democrats, who said the move would be hypocritical, as Republicans staunchly defended the blue slip process while Obama was in office.