One of the main attractions of the reform is that it would mean that we would once again have true national campaigns, with candidates focusing on all 50 states, instead of just the handful of swing states like Ohio that have decided many of the recent presidential elections.

“You might think Republicans would be opposed because they’ve benefited from the current system in two of the last five elections,” said Hertzberg, referring to 2000 and 2016. But he noted that one of Donald Trump’s tweets this week suggested that he might not be opposed to the new system: “If the election were based on total popular vote,” Trump tweeted, “I would have campaigned in N.Y. Florida and California and won even bigger and more easily.”

Pat Rosenstiel is a lifelong Republican, the owner of a branding company and the senior national adviser to the National Popular Vote, which is the formal name of the effort. He says interest in it has exploded since November 8.

“We usually get two or three people a day using our website to send letters to their legislators in favor of the plan,” said Rosenstiel. “But since the election, 100,000 letters have been sent to legislators across the country.”