More Americans approve of the impeachment investigation into President Donald Trump than disapprove of it, though only about a third say the inquiry should be a top priority for Congress, according to a new poll from The Associated Press-NORC Center for Public Affairs Research.

That solid, if measured, support serves as a warning sign for Trump’s White House and reelection campaign, which have insisted that pursuing impeachment will end up being a vulnerability for Democrats heading into 2020.

But the findings present some red flags for Democrats, too: More people say House members are motivated mainly by politics rather than by duty as they investigate the Republican president’s dealings with Ukraine and whether he abused his office or compromised national security when he tried to pressure the country to dig up dirt on a political rival.

And assessments of the president’s performance generally have remained remarkably stable even as the investigation has unfolded at a rapid clip.

Overall, 47% said they support the impeachment inquiry, while 38% disapprove.

Still, 53% of Americans think the House is acting mainly on a political motivation to challenge Trump’s presidency. That compares with fewer, 43%, who say it’s acting more in good faith on its responsibility to investigate the executive branch.