Former House Speaker Newt Gingrich's (R-Ga.) camp blasted President Obama's reelection announcement Monday, highlighting the potential for Obama to raise upwards of $1 billion for his 2012 race.

"With their announced goal of raising a billion dollars in order to drown out their opposition, one thing is certain: it begins and ends with political extortion," Gingrich spokesman Rick Tyler said in a statement reacting to Obama's announcement.

The president made his bid for a second term official early in the day, distributing a video message to supporters.

In the video, titled "It begins with us," a series of Obama supporters talk about the need for a second term for the incumbent Democrat. In an accompanying email message, Obama wrote, "Today, we are filing papers to launch our 2012 campaign ... [E]ven though I'm focused on the job you elected me to do, and the race may not reach full speed for a year or more, the work of laying the foundation for our campaign must start today."

The former House speaker is the latest rumored 2012 hopeful to react to Obama's online reelection announcement Monday.

Former Minnesota Gov. Tim Pawlenty released a video of his own earlier in the day, highlighting the economic downturn and former Massachusetts Gov. Mitt Romney tweeted, "@barackobama I look forward to hearing details on your jobs plan, as are 14m unemployed Americans."

Once Obama files with the Federal Election Commission, his 2012 fundraising efforts can begin in earnest. Both Obama and Vice President Joe Biden have met in recent weeks with supporters at events billed as non-fundraisers that have hosted a number of top donors whose financial support is likely to come quickly to the campaign.

In addition, the president has a major fundraiser scheduled for mid-April in Chicago, which could bring in millions for his campaign.

-Michael O'Brien contributed to this report.