MIDDLETOWN, N.J. (CBS) - US Sen. Robert Menendez (D-NJ) is up for re-election next year, and New Jersey’s Republicans, of course, hope to mount a tough challenge.

Today, we’re learning more about a potential top GOP candidate from Monmouth County.

Longtime New Jersey state senator Joseph Kyrillos (above) has formed an exploratory committee to see if he’s got a shot at keeping Menendez from a second full term.

“Anytime the economy is as bad as it is, there’s always a chance that incumbents can lose,” says political analyst Ben Dworkin, the director of the Rebovich Institute for New Jersey Politics at Rider University.

Dworkin says Kyrillos is tight with Chris Christie — having served as chairman of his gubernatorial campaign — and he’s likely considering a run with the governor’s blessing.

But Kyrillos first has to get his name out there.

More Republicans are likely to throw their hats in the ring, possibly including Tom Kean Jr., the state senator who unsuccessfully challenged Menendez in 2006.

And Ian Linker, a North Jersey lawyer, already has declared his candidacy.

Then there’s the question of cash: it takes at least $15 million to run a competitive race like this one.

“Bob Menendez should not be underestimated by any stretch,” says Dworking.  “I think he will have the benefit in 2012 of running with Barack Obama, who despite the economic situation continues to be rather popular here in New Jersey.”

Reported by Ian Bush, KYW Newsradio 1060