All but one of the Connecticut State Police cars are unmarked. They use everything from Corvettes to SUVs.
They used to be predominately Ford Crown Victorias, but in the last three or four years I’ve seen mostly Chevy Malibus and Chevy/GMC SUVs. At least South of New Haven. Fords may still be dominant in rural areas and non-highway duty.
Just speculation, but I think that the only reason they have the one marked car is so that they could cash in on the fad for model state police cars that arose in the Nineties. A plain brown car with no lights or outward equipment probably wasn’t appealing to collectors.