More than two out of every three U.S. citizens in a recent poll say they are very or somewhat concerned about the security of the nation’s electoral system.

The Economist/YouGov poll was conducted amid Republican presidential nominee Donald Trump’s recent claims that the November election is “rigged.”

Seventy-two percent of respondents said they were very or somewhat concerned about the security of the electoral system while just 21 percent were either not very concerned or not concerned at all.

The survey found that two out of five respondents (42 percent) said they believed that Russia was attempting to influence the U.S. presidential election.

Last week, the White House officially accused Russia of meddling in U.S. elections. Russian President Vladimir Putin has denied any hand in the recent cyberattacks on Democratic groups and voter registration systems.