Republican National Committee Chairman Reince Priebus called Donald Trump's firing of campaign manager Corey Lewandowski a "good sign" for where his campaign stands a month out from the party's convention, during a Monday interview with Fox News.

"When you look at the shift from a primary election over to the general election, this is sort of the professionalization that continues the pivot to the presidential — I think it's a good sign I think for the campaign," Priebus told host Greta Van Susteren.

Priebus applauded Lewandowski for how he has handled the news. The former campaign head did a number of network TV interviews following the firing. Priebus said Lewandowski handled himself very well and was "very classy" by pledging his support to Trump in the general election.

The chairman also said the RNC is in better shape this election year than it was four years ago when GOP nominee Mitt Romney went up against President Obama.

"I think if Mitt Romney had the RNC of today, he would have won," Priebus said.