Regents of the Maryland state university system voted against merging the flagship College Park campus with the professional campus in Baltimore this afternoon, effectively shooting down a politically charged proposal from a powerful state politician.

Maryland Senate President Thomas V. “Mike” Miller Jr. (D-Calvert), an avowed advocate of a merger, asked the regents of the University System of Maryland last spring to prepare a report on the pros and cons of combining the two schools.

Regents rejected the merger, instead adopting a report that recommends forming a “strategic alliance” to support greater collaboration between the two campuses.

University System of Maryland Chancellor Brit Kirwan seemed to hit upon the rationale for rejecting a merger when he explained the reasoning behind the “alliance”: A merger would cost money, a lot of money, at a time when Maryland has little to spare. A comparatively modest strategic alliance would potentially accomplish the same thing “without incurring the excessive overhead of unifying the two large and somewhat incompatible bureaucracies” of the two universities, Kirwan said.

The proposal polarized the state. Supporters of Baltimore — both the city and the university campus there — spoke emphatically against a merger, warning that a combined operation would deal a grave economic blow to Charm City. Supporters of College Park — both the city and its flagship campus — argued that the state could only benefit from having a single powerhouse university, two halves combined into a whole.

The University of Maryland, College Park is the state’s flagship public university, with 35,000 students and a $1.6 billion budget. It resembles most of the nation’s other flagships in many ways, save that it lacks law and medical schools.

The University of Maryland, Baltimore, is a professional campus of 6,000 students with a $1 billion budget, anchored by nationally ranked law and medical schools.

Most flagships, as I said, have law and medical schools. Some do not. Neither Berkeley, the University of Illinois nor the University of Texas has its own medical school. College Park is one of six state flagships with neither a law nor a medical school.

Does that matter? Well, law and medical schools are large, nationally competitive enterprises. Medical schools engender massive sums of sponsored research. The Baltimore campus, though far smaller in enrollment and faculty, produces as much annual research funding — more than $500 million — as does College Park.

Supporters of the merger noted that it would have spawned the 10th-largest research institution in higher education, in terms of research funding.