Kyrillos blames Menendez, and Obama, for not creating enough jobs. Menendez says Kyrillos, just like the presumptive GOP presidential nominee, wants to cut taxes for the wealthy at the expense of the middle class.
But the race took an unexpected turn after Romney picked U.S. Rep. Paul Ryan of Wisconsin, who heads the Budget Committee and supports sweeping changes to entitlement programs, as his running mate. Suddenly wonky discussions about health care and government programs became part of the debate.
"I think it crystallizes the election from one that Republicans would have liked to have - make it a referendum on Obama - to a choice election," Menendez said in an interview in Camden last week. "There are clearly two different visions here."
Pollsters expect Obama to win New Jersey in November, and so far they're betting that Menendez, who has $10.3 million in campaign cash on hand, will secure reelection to his second full term. New Jersey hasn't elected a Republican senator in 40 years.
But Menendez's job-approval rating is somewhat lackluster - below 50 percent, according to polls. Kyrillos, a 24-year veteran of the Legislature and a close ally of Gov. Christie, sees that as an opening.
"It's not a normal election year," Kyrillos said over an egg-white omelet at the New Monmouth Diner in Middletown. "I'm willing to concede that the president, at this moment in time, looks like he could win [in New Jersey]. But I don't think it will be a landslide."
Menendez, 58, of North Bergen, has been a vocal supporter of the president's health-care overhaul, despite polls that show a majority of Americans don't support it. While some Democrats have avoided discussing the law in stump speeches, Menendez told Camden community health advocates last week that he was proud to have helped pass it.
"We come together not only to celebrate some direct federal assistance, but also really to celebrate . . . a law . . . the Affordable Care Act, that makes this funding possible," Menendez said at an event honoring Camden health providers who were awarded $7.5 million in federal grants for community health care.
Kyrillos, 52, of Middletown, said he wants to repeal the health-care law, which was upheld by the U.S. Supreme Court in June.
Though he agrees with some of the its provisions, including barring insurance firms from refusing to provide insurance to those who have preexisting medical conditions, he believes the health-care act is too expensive.
He faults Menendez for his support of Obama's agenda, which he says hasn't fixed the economy fast enough.
"It's no one person's fault, but where have you advocated? How have you voted? What policies have you embraced?" Kyrillos said. Menendez "is part of a failed administration."
As for Medicare, the government-run health-care program for the elderly, Ryan wants to transform it into a voucherlike program, though he has more recently offered that as an option to the current system.
Democrats, including Menendez, say the vouchers - which would be tied to inflation, but not the generally higher medical inflation - wouldn't cover the rising cost of health care, leaving seniors to pay more as the years go on.
Kyrillos said that Medicare and other entitlement programs must change and it's dishonest to tell voters otherwise. The country can't afford them as they are, he said.
"It's not about ideology, it's not about partisanship, it's about mathematics," Kyrillos said. "These systems will be changed no matter who the president is and no matter who the senators are."
He supports Ryan's latest idea to allow people to choose traditional Medicare but also allow them the option of taking a voucher to buy their own care.
Kyrillos has also said he's willing to raise taxes to shore up the country's finances, but he offered no specifics other than to dismiss the idea of taxing millionaires.
He voted against a bill in the state Legislature this year that would have raised tax rates on those making more than $1 million, and he opposes Obama's push to allow the Bush tax cuts for higher-income earners to expire.
He said he would be willing to close deductions and loopholes.
"I'm not sure which are the right ones, but I know that bright people from both sides of the aisle need to decide," he said.
Kyrillos declined to sign the Americans for Tax Reform pledge, in which signers agree to vote against tax increases. It's a rare move for a Republican running for federal office, although more Republicans have been bucking the pledge since the economy tanked in 2008.
Kyrillos doesn't sign pledges, said Meaghan Cronin, his communications director.
Kyrillos' has $1.9 million cash on hand, about a fifth of Menendez's haul. Since both will be spending in the uber-expensive New York and Philadelphia media markets, Kyrillos has less money, and therefore less time, to make his case to voters, said Patrick Murray, political analyst at Monmouth University.
Christie can help Kyrillos raise money, but Murray is skeptical that the Republican governor can do more.
"You can't impart your own popularity onto somebody else," he said.
Contact Joelle Farrell at 856-779-3237, firstname.lastname@example.org, or follow on Twitter @joellefarrell.