President Trump Donald John TrumpFederal prosecutor speaks out, says Barr 'has brought shame' on Justice Dept. Former Pence aide: White House staffers discussed Trump refusing to leave office Progressive group buys domain name of Trump's No. 1 Supreme Court pick MORE’s approval rating dipped slightly among Republican voters, though is relatively steady among voters overall, according to the latest Hill-HarrisX poll released Friday.

The nationwide survey shows 83 percent of GOP voters saying they approve of the president’s job performance, marking a 2-point drop from an identical poll conducted Aug. 18-20.

Trump’s overall approval rating remains steady, ticking up 1 percentage point from the previous poll to 47 percent, while 53 percent disapprove.

The president's approval rating rose 3 points among independent voters compared to the previous poll; he now is supported by 46 percent of independents in the poll.

Former South Carolina Gov. Mark Sanford Mark SanfordOn The Money: Business world braces for blue sweep | Federal Reserve chief to outline plans for inflation, economy | Meadows 'not optimistic' about stalemate on coronavirus deal Trump critic Sanford forms anti-debt advocacy group Republicans officially renominate Trump for president MORE (R) last week became the third Republican to launch a bid to challenge Trump for the GOP's presidential nomination in 2020.

He joins 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) and former Rep. Joe Walsh Joe WalshSunday shows preview: Protests continue over shooting of Blake; coronavirus legislation talks remain at impasse Republicans officially renominate Trump for president Tucker Carlson responds to guest correcting pronunciation of Kamala Harris's name: 'So what?' MORE (R-Ill.) in announcing a primary campaign against Trump, who remains widely popular in the party.

Sanford insisted Wednesday that his presidential bid isn’t about hurting Trump’s chances for reelection, but rather about improving the ideas of the Republican Party as a whole.

All three challengers face an uphill battle in seeking to take on Trump. Some states, including South Carolina and Nevada, have moved to cancel their primary elections recently.

The Hill-HarrisX survey was conducted online among 1,000 registered voters between Sept. 11-12 with a margin of error of plus or minus 3.1 percentage points.

—Tess Bonn