(Larry Marano/WireImage/Getty Images)

Charlie Crist, the former Republican governor of Florida, has officially switched his party affiliation, three months after speaking at the Democratic National Convention in North Carolina.

Crist made the announcement on Twitter late Friday night, including a picture of him holding up a Florida voter registration form with his wife, Carole.

"@charliecristfl: Proud and honored to join the Democratic Party in the home of President @BarackObama!"

The Tampa Bay Times reports he signed the papers switching his party affiliation from Independent to Democrat at a White House holiday party.

Crist, who has formerly referred to himself as a "Reagan Republican" and "Jeb Bush Republican," was elected to that state's highest office in 2006 as a member of the GOP. His record in the state was fairly moderate; on one hand he espoused tough-on-crime rhetoric, spoke against same-sex marriage, opposed progressive gun control laws and raising taxes. But he was also an advocate for higher teacher pay and passed legislation mostly in favor of abortion rights, despite labeling himself as pro-life.

In 2010 he dropped the party during an unsuccessful run for Senate when he faced a primary challenge from the right in the form of Marco Rubio, who went on to take the seat. Crist has remained an independent since, although he has gradually ramped up ties to the Democratic Party and endorsed President Obama's reelection bid.

"I've had friends for years tell me, 'You know Charlie, you're a Democrat and you don't know it,'" he told the Times on Friday, adding that his decision was based on the rightward shift in the Republican Party.

"What changed is the leadership of the Republican Party," he said. "As I said at the convention, I didn't leave the Republican Party, it left me. Whether the issue was immigration, or education, or you name it - the environment. I feel at home now."

The switch has increased speculation he may attempt to reclaim his old position as state executive from current Gov. Rick Scott, a move long anticipated by Florida conservative groups.

"Charlie Crist's first official act as a Democrat was to tell a lie about why he is now pretending to be one," the state GOP said in a statement. "The truth is that this self-professed, Ronald-Reagan Republican only abandoned his pro-life, pro-gun, conservative principles in 2010 after he realized that Republicans didn't want to send him to Washington D.C. as a senator, especially after he proved he couldn't do the job as governor."

Crist's possible run is a gamble, as he would also face a challenge from other Democrats vying for the gubernatorial seat.