Kamala Harris' Chances of Beating Trump Plunge in Nate Silver Forecast

Vice President Kamala Harris' chances of beating Donald Trump in November have plunged in recent weeks, according to a new forecast from pollster Nate Silver.

Silver's October 14 forecast showed that the Democratic presidential nominee's chances of winning the Electoral College had plummeted to 51.8 percent—dropping by about 6 percentage points since late September.

The same forecast showed Trump's likelihood of winning to be at 47.9 percent.

Harris' steep drop in two weeks comes as new polls show Trump gaining ground in crucial swing states. In the past week, the former president has made gains in 19 states, according to Silver's forecast.

"There's been a slight upward trajectory for Trump in our forecast over the past week.," he said in an update last week," Silver wrote on Monday.

Many polls from key swing states show one of the candidates ahead by razor-thin margins, which are often within the polls' margins of error.

Silver, a leading polling analyst and founder of polling aggregator FiveThirtyEight, which he is no longer affiliated with, has his own model to predict the outcome of the election, called the Silver Bulletin.

The model builds on the methodology of the FiveThirtyEight election model and integrates polling data, economic indicators and historical trends to predict each candidate's likelihood of victory.

At present, Silver's model puts Harris narrowly ahead of Trump overall, which is in line with other national polls.

Newsweek contacted the Harris and Trump campaigns via email for comment outside regular working hours.

The latest national poll from The New York Times/Siena College, conducted between September 29 and October 6, showed Harris ahead of Trump by 3 percentage points, 49 to 46 percent, in a two-way matchup.

Harris' chances of success hinge on her ability to win swing states. The vice president needs 44 electoral votes from toss-up states to secure victory, while Trump needs 51.

If Harris won Pennsylvania, Michigan, Wisconsin and Nebraska's 2nd District, she would reach the electoral threshold required to win.

Silver's latest forecasts showed that Harris was narrowly on track to achieve this, although he said in late September that he believed the vice president's campaign should be nervous about Wisconsin and Pennsylvania.

Although Silver described Michigan as a relatively safer bet for Harris, RealClearPolitics' poll tracker last week showed that Michigan had flipped in favor of Trump for the first time since July 29.

Silver has repeatedly said that this election is looking to be the tightest he's ever observed.