Forty percent of Republicans in Iowa say they hope President Trump Donald John TrumpOmar fires back at Trump over rally remarks: 'This is my country' Pelosi: Trump hurrying to fill SCOTUS seat so he can repeal ObamaCare Trump mocks Biden appearance, mask use ahead of first debate MORE faces a primary challenge in 2020, according to a poll published Monday.

But the CNN–Des Moines Register–Mediacom poll found that another 41 percent of Iowa Republicans say they don't want Trump to face a primary challenge, while the remaining 19 percent say they aren't sure.

ADVERTISEMENT

Among those who are hopeful for a primary challenge to Trump, 63 percent say they approve of his job as president, according to an accompanying CNN report.

That's below the 97 percent who approve of Trump among those who said they did not want a primary challenger and the president's overall 81 percent approval rating among Republicans in the state.

Of those Iowan Republicans who wanted a GOP primary challenger, just 38 percent say they will definitely vote for Trump in 2020.

The poll's results were based on interviews with 400 registered Republicans from March 3 to 6. The poll has a margin of error of 4.9 percentage points.

If Trump were to face a competitive primary challenger, it would be the first notable primary challenge to an incumbent president since 1992, when Pat Buchanan challenged then-President George H.W. Bush.

Former Massachusetts Gov. Bill Weld William (Bill) WeldRalph Gants, chief justice of Massachusetts supreme court, dies at 65 The Hill's Campaign Report: Biden visits Kenosha | Trump's double-voting suggestion draws fire | Facebook clamps down on election ads Biden picks up endorsements from nearly 100 Republicans MORE (R) announced last month that we was forming an exploratory committee for a potential 2020 bid, making him the first Republican to take that step in a possible challenge to Trump.

Other Republicans are also considering their own bids, including former Ohio Gov. John Kasich and Maryland Gov. Larry Hogan.