As the youngest members of the millennial generation became old enough to vote in this year's U.S. presidential election, states and social media platforms poured efforts into online registration, hoping to attract these tech-savvy voters who now rival Baby Boomers as the country's largest demographic.

With Election Day on the horizon, political experts are skeptical that a record number of millennials who signed up to vote will actually result in the 18-34 year-old age group turning out at the polls in proportion to their relative size of the U.S. population.

Millennials make up approximately 31 percent of U.S. citizens eligible to vote, according to the Pew Research Center, on par for the first time with Baby Boomers, who are typically aged 52-70 years old. There are an estimated 225.8 million eligible U.S. voters.