(CNN) - Democratic Rep. Tammy Baldwin of Wisconsin on Tuesday announced a bid for the Senate in 2012.
In a three-minute web video, the six term congresswoman likened herself to retiring Democratic Sen. Herb Kohl and former Democratic Sen. Russ Feingold, who lost his reelection bid in 2010.
She pointed to her opposition to the deregulation of Wall Street and the war in Iraq as examples of her progressive credentials. Wisconsin is a battleground state President Barack Obama won with 56 percent of the vote in 2008. But Republicans made significant gains during the 2010 election, capturing a Senate seat and the governor's mansion.
"Just like Herb Kohl, I've made standing up for the middle class my top priority and I've never hesitated to speak my mind," Baldwin said in the video. "The fact is we have to create jobs and get the economy back on track, and it's time politicians looked out for seniors, working families and the middle class instead of protecting the profits of big oil and Wall Street."
With Feingold passing on another Senate bid last month, Baldwin is the early frontrunner on the Democratic side. Democratic Rep. Ron Kind and former Democratic Rep. Steve Kagen are also considering bids.
On the Republican side, former Rep. Mark Neumann, who won the backing of the conservative Club for Growth Political Action Committee last week, is running for the seat and former Gov. Tommy Thompson is mulling a run.
If elected, Baldwin would be the only openly gay member serving in the Senate.