On Monday, we wondered if Taylor Swift's first major political endorsements could move the needle. On Tuesday (Oct. 9), it seems we may have an answer. According to figures provided to Billboard by Vote.org, as of Tuesday morning, Swift's Instagram post in support of U.S. Senate candidate and former two-term governor Phil Bredesen and incumbent U.S. House member Rep. Jim Cooper has "significantly" driven up voter registration among 18- to 29-year-olds in a two-day period.

Vote.org is a nonpartisan site that uses technology to increase voter turnout by offering voter registration and absentee voter tools and a way to verify your voter registration status without tracking people's party registration. The site reported that since Swift urged her 112 million followers to vote on Sunday, they've noted a "massive spike of voters registering nationwide." While a spokesperson said in a statement that there are several factors contributing to the increase -- Tuesday is the last day to register to vote in 13 states -- a large majority of new registrations since Swift's action have been from people between 18-29.

Among that group, around 102,000 out of the 240,000 total new registrations came in the 48 hours after Swift's post. As of noon ET on Tuesday, voter registration figures in Tennessee jumped dramatically, from just 341 in January to 2,811 in September and 7,554 so far in October, according to Vote.org. Nationwide, voter registration climbed from 12,846 in January to 49,030 in July, 190,178 in September and 240,329 to date in October. Since Sunday, voter registrations among 18- to 29-year-olds led all age groups by far (70,928), with 25- to 29-year-olds a distant second (32,019).

And while Vote.org said it can't definitively attribute all those new registrations to Swift, the surge is among voters firmly in her demo, whose registration numbers almost doubled overnight. "We always have a spike in October. People wait until the deadline to register," according to Vote.org. "However, Taylor Swift’s visibility on this issue is driving a lot of coverage of voter registration and it’s reaching many of her fans who would not otherwise be following news like this. Ultimately, this might have been what pushed many of those 18- to 24-year-old voters over the line to register."

For insight into how Swift's post has inverted the numbers from the 2016 presidential election, the full registration figures for October 2016 had voters 30-39 leading registrations by a larger margin (112,093) over 18-25 (87,876) and 25-29 (78,016). BuzzFeed News originally reported on the Swift spike, noting that a spokesperson for Vote.org said the site had seen a big uptick in the number of visitors since her post, with 155,940 unique visitors in 24 hours, second only to the number of visitors who checked in on National Voter Registration Day (Sept. 25), when it had 304,942 unique visitors.

"To have someone of her stature and with such a large microphone to step up and actually reinforce what we already know here is definitely going to boost the morale of people who have been told Tennesseans are divisive," Mary Mancini, chair of the Tennessee Democratic Party, told BuzzFeed. "Having her come out and say this so publicly will make people sit up and say, ya know what, I’m not alone here."

While Swift has spoken out in the past on a number of issues close to her heart -- the March for Our Lives campaign for commonsense gun laws, LGBTQ Pride Month -- she notably stayed on the sidelines during the contentious 2016 presidential election when many fans wanted her to weigh in. In her Instagram post, she strongly endorsed Democrats Bredesen and Cooper, writing, "In the past I’ve been reluctant to publicly voice my political opinions, but due to several events in my life and in the world in the past two years, I feel very differently about that now," Swift, 28, wrote while staying vague about what those precipitating "events" were. "I always have and always will cast my vote based on which candidate will protect and fight for the human rights I believe we all deserve in this country."

Swift's post drew quick rebuke from Republican politicians, including President Trump, who told reporters on Monday that he likes her music "about 25% less now." At press time, Swift's post had nearly 1.9 million likes.