He called Iowa and Virginia, where Clinton’s lead has narrowed from 45 to 34 percent a month ago to 45 to 39 percent, a metaphor for what’s happening in the presidential race. A month ago, Clinton was “riding the post-convention wave that gave her double-digit leads in many polls.”

The fresh poll numbers reflect a new reality of a tighter race for the White House.

“Leads for Donald Trump in Georgia and Iowa and a virtual tie in Colorado plus a 6-point lead for Clinton in Virginia represent a major improvement overall for him in these states,” Brown said.

Another change is that Trump has improved his hold on the Republican base.

“Throughout the campaign, Clinton has been able to get more Democrat support than Trump’s Republican support,” Brown said. “In Georgia and Iowa, Trump does better on that score.”

He also pointed out that Trump has an edge among independent voters, often the key swing constituency, in the four states polled.