The spread of coronavirus during a presidential campaign year is a potential nightmare for election officials supervising crowded voting centers, communal touchscreens and older poll workers. As concerns grow that the virus could keep people from the polls, some tech executives and government officials are looking more closely at how quickly online voting could be ramped up in the U.S.

So far, online voting has been tried in limited situations, including a small pilot program in West Virginia in 2018 and a local election in Washington state last month. There are huge challenges to broader adoption. For one, the technology is far from proven. Government officials and security experts worry that the process could be vulnerable to hacking. In addition, the decentralized nature of U.S. elections means individual systems would have to be set up across thousands of local jurisdictions.