Most Americans want a special prosecutor to investigate contacts that officials on President Donald Trump‘s campaign made with Russian officials, according to a new poll.

The CNN/ORC survey released Monday showed that about two-thirds of Americans think a special prosecutor should be appointed to conduct the inquiry, while 32% say Congress can conduct a sufficient investigation. More than half of those surveyed are at least somewhat concerned about contacts between the President’s campaign and Russia, a controversy that has lingered during the early weeks of Trump’s administration. Attorney General Jeff Sessions recently announced he would recuse himself from investigations into the Trump campaign’s ties with Russia, after revelations that he failed to disclose contacts with Russia’s ambassador during his confirmation hearings.

At least 70%, including 47% of Republicans, at least somewhat agreed with the intelligence community’s conclusion that Russia sought to influence the outcome of the election. But the poll also indicated that the steady stream of news reports about contacts with Russia have not had a major impact on the Trump’s approval rating. Some 45% of Americans approve of the job President Trump is doing.

The survey of 1,025 people conducted March 1-4, had a margin of error of plus or minus 3 percentage points.