The U.S. Supreme Court has declined to take a case challenging limits on party spending. 

Late last year, the Republican National Committee, along with former Rep. Joseph Cao (R-La.), asked the high court to hear a challenge to the constitutionality of limits on what political parties can spend in coordination with candidates.  

The decision by the court on Monday not to grant cert in the case comes as something of a surprise to observers and a relief to campaign finance watchdogs. 

In the wake of the high court's landmark decision last January in Citizens United v. FEC, which paved the way for corporate spending on campaign ads, watchdogs have worried about subsequent court challenges to current campaign finance law.

A federal appeals court has already rejected the GOP's argument in Cao v. FEC, and last summer, the Supreme Court also declined to hear a challenge to the ban on so-called soft money contributions to political parties. 

The decision not to hear the case was hailed by the Campaign Legal Center, a group fighting efforts to loosen campaign finance restrictions. 

"This morning the Supreme Court deferred to precedent and declined to hear this attack on the longstanding limits on party coordinated spending," the center's attorney, Tara Malloy, said in a statement. 

Malloy said the challenge "would have blown huge loopholes in the federal campaign finance laws and enabled large-scale circumvention of the individual contribution limits."