Trump can't seem to win over women voters. It may cost him a second term.

• With just over three weeks until Election day, likely female voters overwhelmingly prefer Democratic nominee Joe Biden over President Donald Trump.
• According to the Center for American Women and Politics at Rutgers University, Biden leads among women voters by an average of 18.6 percentage points in the 46 national polls tracked by the organization.
• Eligible women voters outvoted their male counterparts by 4 percentage points in 2016, according to Pew Research Center.

With almost 3 weeks left until the presidential election, women voters appear to have a clear preference: Joe Biden, by a staggering amount.

The Center for American Women and Politics at Rutgers University tracks the gender gap in support between major party candidates in polls, both nationally and in battleground states. In each of the 46 national polls tracked by the organization since May, Biden has led with women by an average of 18.6 percentage points.

Though President Donald Trump is currently trailing Biden in key states among all likely voters by a margin of 1-5 percentage points, his margin of support among women is abysmal in battlegrounds.

In Florida and Pennsylvania, two states which Trump desperately needs to win, he trails among female voters by 18 and 15 points respectively. Of every state flipped by Trump in 2016, Florida and Pennsylvania contain the two highest number of electoral votes, combining for 49.

Another reason for the Trump campaign to take women voters more seriously? They vote at higher rates than men.

According to CAWP, "in every presidential election since 1980, the proportion of eligible female adults who voted has exceeded the proportion of eligible male adults who voted."

In 2016, according to Pew Research Center, women voted more than men in the presidential election by 4 percentage points. Among Black eligible voters, that gender gap is even greater: 10 points.

In mid-August, Trump tweeted that his support from the "suburban housewife" demographic was secure. That same day, Trump said in a press conference that Biden and Kamala Harris, his vice presidential pick, would "destroy suburbia."

According to a new report from Pew Research Center, Trump's inflammatory remarks failed to sway suburban voters, especially suburban women.

While he is just 5 percentage points behind Biden among men in the suburbs, he is 19 points behind the Democratic nominee with female suburban voters.

The same Pew survey estimates that the two presidential candidates are tied among married women. Unmarried women, however, prefer Biden by 35 points.

If the Trump campaign plans to sway over women voters before the election, it needs to do it soon to have any real effect.

As of October 9th, about 8 million ballots have already been cast. At this point in 2016, about a month away from the election, only 75,000 mail-in votes had been cast. According to voting rights experts, voting by mail is expected to make up 50% to 70% of the total vote in November.

In 2016, Trump won a seat in the Oval Office despite losing among women voters to Hillary Clinton by 15 points, according to Pew Research Center. If he hopes to win a second term in 2020, he may need to rethink that strategy and fast.