The two also spent several minutes describing how they would help the middle class, but both struggled to define who constitutes the middle class.
Menendez said it's families who work hard, have a home, want their children to go to college and not be one illness away from bankruptcy. Kyrillos said it's "nearly everyone."
Kyrillos mentioned former Gov. Jon Corzine at least three times during the debate, trying to tie Menendez, whom Corzine appointed to the Senate, to the defeated Democrat.
"Let me bring back (former Republican Gov.) Christie Whitman and the bond issue that exploded state debt," Menendez replied.
Menendez, 58, is seeking a second six-year term. His opponent is a 52-year-old commercial real estate broker who chaired Mitt Romney's presidential campaign in New Jersey in 2008. New Jersey hasn't elected a Republican to the U.S. Senate since the '70s.
Menendez entered the campaign with other advantages over Kyrillos. Menendez is far better funded and has more name recognition among voters. He comes from heavily populated Hudson County, and has President Barack Obama anchoring the ticket.
Kyrillos is from Monmouth County and counts Gov. Chris Christie among his long-time friends. Both Christie and former Florida Gov. Jeb Bush are expected to be campaigning with Kyrillos this month as he tries to gain traction in a race that's not getting a lot of attention.