AUSTIN — Dr. Mike McKinney's five-year tenure as chancellor of Texas A&M University was marked by turmoil and controversy, but his unexpected departure has exacerbated tension among faculty, influential alumni and lawmakers who keenly fear that politics will play an outsized role in choosing his successor.

McKinney, a medical doctor, former state legislator and chief of staff to Gov. Rick Perry, announced this week he intended to resign after several rocky years in which he was vilified publicly by faculty and criticized in private by university regents and a Perry campaign supporter.

In a public statement Tuesday, McKinney announced he would retire July 1. Thursday, the Dallas Morning News and Texas Tribune reported that McKinney was asked to step down after meeting last week with Board of Regents chair Richard Box and a second regent who told him it was time for a change.

McKinney did not return calls to his office for comment Thursday.

State Sen. Judith Zaffirini, D-Laredo, who chairs the Texas Senate Higher Education Committee, said she feared that McKinney was asked to resign because he did not move quickly enough to implement controversial policies advocated by Perry.

She also expressed concern that Perry would try to influence the regents' selection of McKinney's successor, noting that he had pressured A&M regents to hire former U.S. Senator Phil Gramm as president over Robert Gates, now U.S. Secretary of Defense. Perry also pushed for former State Sen. John Montford's selection as University of Texas chancellor when regents chose Francisco Cigarroa, she said.

“The regents might have a difficult time finding a real star, given the ongoing controversy,” she said.

She said she hoped regents would search nationally for “an academician who is stellar and will promote A&M as a national research university.”

That message was echoed Thursday by the A&M Faculty Senate, which appealed to the Board of Regents for a national search for McKinney's replacement.

Chancellor candidates “should have as their vision the continued improvement of the university and system” and pledge to support A&M's strategic plan, Vision 2020, to improve its national status as a research institution, said incoming Faculty Speaker, Dr. Michael Benedik.

Benedik summed up the mood on campus: “Worried. The faculty is concerned because although we had our differences, he also worked hard to limit the implementation of bad policies.”

He was referring to the “Seven Breakthrough Solutions” advocated by Perry and an influential campaign contributor, Austin businessman Jeff Sandefer.

Sandefer, a former business instructor at the University of Texas at Austin, devised the “Seven Breakthrough Solutions” as a pathway to make higher education more efficient by separating research and teaching functions.

The solutions call for evaluating professors according to the number of students they teach and rewarding them financially solely on student evaluations.