"It is with great sadness that I received the news today of the passing of my friend and Chief of Staff Steve Vermillion," Rivera said on the House floor Friday. "For nearly 25 years, I have known Steve as a friend, family man and committed public servant.
Sensenbrenner also spoke, and said that Vermillion made a "great contribution" to the country through his service.
"He was a man of unquestioned ability, a man of deep integrity, and a man of great commitment to his principles and love of this country and the democracy that we have built and nurtured over the last 230-plus years," he said.
Vermillion is survived by his wife, Jennifer, and two children.