The "Trump Train" is headed straight for the general election and picking up supporters along the way, including more millennial voters.

According to a Fox News poll released Wednesday afternoon the billionaire has significantly closed the gap with Clinton among Gen Y voters, and is now leading among Gen-Xers by double digits.

In a head-to-head matchup, Clinton leads Trump among millennials by 11 percent, 46 to 35 percent, respectively. While Clinton still holds a double-digit lead, it's down 7 points from a Fox News poll released on March 23 that showed an 18-point margin.

While some have warmed up to the idea of voting for Trump, (he increased his support among millennials by three percent), even more have lost any faith in voting for Clinton (her support has declined by four points).

It's possible that some of these voters are Sen. Bernie Sanders (I-Vt.) supporters who have become disenfranchised by Clinton and the Democratic establishment.

After factoring in the Libertarian candidate Gary Johnson, the gap shrinks to just 9 percent -- 40 percent for Clinton, 31 percent for Trump, and 18 percent for the former New Mexico governor.

Another 5 percent of millennials said they just wouldn't vote.

When the question was asked back in March, 45 percent of Gen Y respondents said they would strongly consider voting for a third-party candidate over either Trump and Clinton, or would not vote at all.