Surrounded by his wife, Demi Moore, Soleil Moon Frye and Sean "Diddy" Combs supporting him via phone, the star officially crossed the one million mark, beating out rival CNN Breaking News shortly after 11 PM Pacific time.
"Where's the champagne, where's the champagne," Ashton said on his Ustream.TV web feed just a short while before reaching his goal. "We've gotta pop the cork on this folks."
CNN, which lost by less than 1,200 followers, quickly congratulated the star.
"Congrats @aplusk. Ashton Kutcher is the first twitter account to reach 1MM followers," someone wrote on their Twitter account page.
The race was a tight one with only a handful of followers separating the two Tweeters as their numbers inched closer to one million on Thursday evening.
"Tell me this isn't better than watching tv," Ashton Tweeted on Thursday, just a few hours before he crossed the finish line. "We get to participate in the entertainment. I feel like I'm directing an episode of punk'd"
Ashton was in the lead for most of the day, but just before 10 PM local time, CNN took over the top spot, leaving the actor to Tweet about the news network's on-air push for more followers.
"Why R they pushing so hard if this doesn't mean anything? It's a changing of the guard. the old way the new way," he wrote, as his followers reported back that CNN was using their live broadcast to seek out new followers.
It was at that point that Ashton jumped on Ustream.TV, speaking live with his fans who rallied around the star.
While Ashton crossed one million followers, earlier in the day it appeared the actor's account was hit by a bug in the run up to meeting his goal.
"Both Ashton @aplusk and myself @ mrskutcher have had our updates blocked for the last 2 hours somebody is playing dirty!" Ashton's wife, Demi Moore, wrote on Thursday afternoon.
Ashton promised if he became the first user to reach 1 million followers on Twitter, he would buy 10,000 mosquito nets, a pledge he repeated on Thursday afternoon.
"I'm calling to have a check made out for $100,000 to the Malaria No More Fund," he wrote.
He also promised that his one-millionth follower would be made into a Sims character.
Related Content from AccessHollywood.com:
PLAY IT NOW: Access Search Engine: Ashton & CNN's Twitter Battle (April 16, 2009)
PLAY IT NOW: Access Search Engine: Ashton's Love Note To Demi (March 25, 2009)