Sen. Frank Lautenberg (D-N.J.) said that potential primary opponent Newark Mayor Cory Booker is "entitled" to run for his Senate seat, but cautioned that Booker will have to prove himself if he does.

"He's entitled to do it," Lautenberg told the Philadelphia Inquirer. "He'll have to stand on his record, and I'm sure he won't be a lone soldier out there drooling at the mouth and wanting this cushy job that we have here."

Booker announced he was looking into a Senate bid in late December, and has faced a firestorm of criticism from Democrats dissatisfied with what many see as a disrespectful way to indicate an interest in the seat.

Lautenberg has not yet indicated his plans for 2014, and though many in New Jersey expect the 88-year-old to retire rather than run for reelection, Booker's decision to come out so early with his intentions was seen by many as placing unnecessary pressure on the incumbent to make a decision.

Though sources from Lautenberg's office have criticized Booker anonymously, the senator himself seemed to indicate he wasn't phased by Booker's intentions.

"I have four children, I love each one of them. I can't tell [you] that one of them wasn't occasionally disrespectful, so I gave them a spanking and everything was OK," he said.

He also insisted he wasn't thinking about politics at this point, and wouldn't say when he planned to make up his mind about running in 2014.