Sen. Robert Menendez (D-N.J.), who finds himself in increasing trouble over his use of flights provided by a Florida doctor who is under investigation, said Monday that his failure to disclose those trips was an oversight caused by his hectic schedule.

"I was in a big travel schedule in 2010," he said Monday in an interview with CNN's Dana Bash -- his first extended comments since his late payments were reported last week. "I was the chair of the DSCC, plus my own campaign getting ready for a reelection cycle. And in the process of all of that, it unfortunately fell through the cracks that our processes didn't catch moving forward and making sure that we paid."