A clear majority of Americans believe President Donald Trump has tried to interfere with the investigation into whether Russia meddled in the 2016 election and possible Trump campaign collusion, a new poll shows. Just one in five support his decision to oust James Comey from the FBI.

Following Comey’s blockbuster appearance before Congress, an Associated Press-NORC Center for Public Affairs Research poll shows 68 percent of Americans are at least moderately concerned about the possibility that Trump or his campaign associates had inappropriate ties to Russia. Almost half of Americans say they’re very concerned. Only 3 in 10 say they’re not that concerned.

Americans largely view the issue along partisan lines. Sixty-two percent of Republicans say they’re not very concerned or not at all concerned about any Russia ties. Though just over half of Americans say they disapprove of Trump’s firing of Comey, the number grows to 79 percent among Democrats. Overall, only 22 percent of Americans support Comey’s dismissal.

Of the six in 10 Americans who think Trump tried to obstruct or impede the investigation, most are Democrats and independents. Only a quarter of Republicans feel Trump meddled in the probe.

The poll began the day before Comey testified publicly before the Senate intelligence committee and continued through Sunday. Three percent of interviews were conducted before the hearing.