RALEIGH, N.C. (AP) — Retired state Rep. Mickey Michaux, whose service in the North Carolina House covered more than 45 years, was appointed on Monday to the state Senate to serve in Tuesday's legislative session.

Gov. Roy Cooper's appointment of Michaux could give Senate Democrats more security in their efforts to uphold Cooper's veto of the Republican state budget. Senate Republicans are trying to override the veto.

The 89-year-old Michaux fills the seat vacated by Sen. Floyd McKissick Jr., a Democrat who resigned last week to join the state Utilities Commission. Cooper, also a Democrat, was required by law to formally appoint Michaux, because he was the pick of Durham County Democrats meeting over the weekend.

“I'm doing it because the (Durham legislative) delgation asked me to do that,” Michaux said Monday in a phone interview.

Michaux said he expects to get sworn in Tuesday and serve briefly as a placeholder in the 20th Senate District seat before stepping down. Three other people are seeking the district's Democratic nomination. Michaux said he anticipates the governor to appoint the March primary winner to succeed him in time for the “short session” this spring.

As an attorney and civil rights activist in the 1950s and 1960s, Michaux counted the Rev. Martin Luther King Jr. among his friends. He first joined the House in 1973 and was elected to 20 two-year terms through 2016, with a stint as a federal prosecutor and unsuccessful runs for Congress sprinkled in between. Michaux served as the House's top budget writer from 2007 to 2010.

Michaux's brief time in the Senate will bring him together with two other powerful black House members during the 1990s and early 2000s. Sen. Dan Blue of Raleigh was elected the first African American speaker in the state history in 1991, while Sen. Toby Fitch of Wilson was the first black member elected House majority leader.