Keselowski began tweeting during the two-hour red flag in Monday night's race. He posted a picture of his view from his race car of the jet fuel fire that stopped racing.
He also answered fans' questions, posted updates on the delay and let other drivers check the weather radar. He also tweeted minutes after wrecking out of the race.
Keselowski's use of Twitter pushed his followers from roughly 65,000 at the start of the race to more than 200,000 by the end of the night.
Penske says all the team's sponsors were excited about Keselowski's tweeting.
The 75-year-old team owner even said he may start using Twitter.