"Electability will come into play for many Republican votes... It’s going to become problematic."

The problem appears to be Gingrich’s appeal — or lack thereof — among independents. But he’s also got problems among Republicans.

Among independents, his numbers are 33 percent positive and 48 percent negative, and among moderates, they are even worse — 30 percent and 52 percent. Even 28 percent of Republicans and 33 percent of conservatives rate Gingrich unfavorably.

Another neutral GOP strategist says that’s enough to call into question his electability.

“Not that many prominent Republicans cross that line of rejection,” said the GOP strategist. “Sarah Palin does. Newt Gingrich comes awfully close.”