RICHMOND, Va. — The political tumult in Virginia widened Thursday as the State Senate’s top Republican faced an onslaught of questions about racist photographs and slurs in a college yearbook that he helped oversee, transforming the Capitol’s nearly week-old crisis into a bipartisan reckoning over personal conduct.

The senator, Thomas K. Norment Jr., who is the majority leader, was the managing editor of the 1968 Virginia Military Institute yearbook, which included slurs and images of students in blackface. Mr. Norment called the use of blackface “abhorrent” while pointing out that he did not take or appear in any of the photographs.

He said he was not surprised that “those wanting to engulf Republican leaders” in the controversies that have rocked Virginia Democrats “would highlight the yearbook from my graduation a half-century ago.”

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As Mr. Norment sought to defuse the fresh controversy, Lt. Gov. Justin E. Fairfax, a Democrat, faced mounting calls from leading members of his party for an investigation into a woman’s allegation that he sexually assaulted her in 2004. Several high-profile Democrats, including some 2020 presidential candidates and members of Virginia’s congressional delegation, said they thought the woman’s account was credible.