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(CNN) —  

Marco Rubio defended his recent Senate vote against barring people on terrorism watch lists from buying firearms on Sunday, saying that the majority of people on those lists have done nothing wrong.

In an interview with CNN’s Jake Tapper on “State of the Union,” Rubio said journalists and people with similar-sounding names to terrorism suspects have been added to watch lists.

“Sometimes you’re only on that list because the FBI wants to talk to you about someone you know, not because you’re a suspect,” Rubio said.

Asked by Tapper if he believes a “majority” of people on the list don’t belong there, Rubio said, “A very significant number of people on that list are on there because they have names similar to somebody else.”

His comments come after Senate Republicans rejected a Democratic-backed measure intended to restrict those watch list members’ ability to legally purchase guns. Other Republicans have made similar due process criticisms of that proposal.

Rubio also complained about the end of the U.S. government’s bulk collection of phone metadata.

The National Security Agency’s bulk metadata collection program officially ended a week ago after lawmakers passed and President Barack Obama signed the USA Freedom Act, which limited the scope of intelligence-gathering efforts.

RELATED: NSA ends bulk phone data collection

Rubio said U.S. investigators are likely to want to know more about who Syed Rizwan Farook – a U.S. citizen and one of the gunmen who killed 14 people in San Bernardino, California – had talked to prior to his attack, and will now be reliant on phone companies’ records.

“If the documents do not exist, they can’t put together the broader picture of who these people are and who they’ve been dealing with,” Rubio said. “Metadata alone is not going to solve all the problems, but it is an important piece of a bigger puzzle that allows you to disrupt potential terrorist plots.”

Rubio also called for U.S. ground troops in the Middle East, as part of a larger coalition made up of mostly Arab forces, to fight ISIS. It’s a position in line with many Republican presidential contenders, but a break from President Barack Obama and Democratic front-runner Hillary Clinton.

“Moving forward, this is not going to be the last attempt to attack the homeland,” Rubio said.