A key Republican state lawmaker said Monday he does not support changing how the state awards its electoral votes before the November election, imperiling a last-ditch push by former president Donald Trump and his allies.

“I respect the desire of some of my colleagues to have this discussion, and I have taken time to listen carefully to Nebraskans and national leaders on both sides of the issue,” state Sen. Mike McDonnell said in a statement. “After deep consideration, it is clear to me that right now, 43 days from Election Day, is not the moment to make this change.”

Nebraska is one of two states — the other being Maine — that awards some of its electoral votes by congressional district. That allowed Joe Biden to pick up an electoral vote in the solidly red state in 2020 by carrying the vote in a competitive House district in the Omaha area.

Trump and his allies have for months advocated for Nebraska to return to a winner-take-all system where the winner of the statewide vote captures all of the state’s electoral votes. Such a move could block Vice President Kamala Harris’s easiest path to win the White House.

Winner-take-all legislation faltered in the Nebraska legislature earlier this year, but Gov. Jim Pillen (R) has said he could call a special session to try again if the proposal gains more support.

Winner-take-all supporters would need 33 votes — every GOP member in the legislature — to overcome an expected Democratic filibuster to pass the legislation. Without McDonnell’s support, Republicans would be at least one vote short.

Pressure ramped up last week, when Sen. Lindsey Graham (R-S.C.), a Trump ally, visited the state to lobby lawmakers and Trump briefly spoke with one of them by phone.

McDonnell was viewed as a key holdout vote after he left the Democratic Party in the spring and joined the GOP. He said at the time he opposed the winner-take-all proposal, but his office more recently suggested he could be open to it.

McDonnell said Monday he has told Pillen “that I will not change my long-held position and will oppose any attempted changes to our electoral college system before the 2024 election.” He added that he would support a proposed constitutional amendment in the next legislative session to let Nebraska voters decide on the issue.