Published: Apr 05, 2011 11:20 PM EDT
Updated: Apr 05, 2011 8:29 PM EDT

WASHINGTON- Debbie Wasserman Schultz, a congresswoman from South Florida and a key White House defender, has been chosen as the next chairwoman of the Democratic National Committee, party officials said Tuesday.

President Barack Obama chose the four-term lawmaker from South Florida to succeed Tim Kaine, who earlier Tuesday announced he would seek a Senate seat in Virginia. The move elevates Wasserman Schultz to a crucial role as Obama looks toward a re-election campaign that will use the DNC to define his likely Republican rivals.

The officials discussed the Wasserman Schultz decision on the condition of anonymity because the announcement was not yet public. Officials said Vice President Joe Biden would announce the news in an e-mail to supporters Tuesday evening.

Wasserman Schultz, who backed one-time Obama rival Hillary Rodham Clinton during the 2008 presidential primary, quickly became a favorite of the Obama campaign. Hailing from the crucial swing state of Florida, Wasserman Schultz became a high-profile advocate for the Obama campaign and then the White House.

"I couldn't have gotten through '08 in Florida without her and she's been there every step of the way through the first term," said Steve Schale, a Tallahassee-based political consultant who ran Obama's Florida operation.

"She is a tireless advocate, she's loyal, but she's not a soldier, she's a leader."

As DNC chairwoman, she is expected to serve as a fierce critic of the yet-unformed Republican field of potential challengers to Obama.

Yet she faces challenges at the committee she inherits.

The DNC remained almost $18 million in debt as the end of February.

The committee spent heavily in an effort to defend majorities in the U.S. Senate and House; Democratic Sen. Harry Reid remains majority leader, but Republicans won a majority in the House and Nancy Pelosi fell from the speaker's role. The committee also shed staff in recent weeks, trying to rein in spending and rebuild its bank accounts.

A rising star in Democratic politics, Wasserman Schultz helped raise millions for the committee during previous election cycles.

In March 2009, the mother of three announced that she had breast cancer. She underwent a double mastectomy.

"Debbie approached cancer the way she approached everything else in her life - head on, 100 miles per hour and never give up," said Schale. The Wasserman Schultz decision was first reported by Politico.

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