It’s still unclear who will enter the race to challenge Massachusetts Sen. Scott Brown, who is among Democrats’ top targets in 2012. But at least one Democrat has formally taken her name out of contention.

Salem Mayor Kim Driscoll, the most prominent woman considering a run, released a statement Tuesday morning declaring that she will not challenge the Republican incumbent, according to a report in the Boston Globe.

“Plain and simple, I do think the seat is winnable, but there is a time and place for everything and I have simply come to the conclusion that for me, at this time, I enjoy my job as mayor of Salem and I believe my work here will require my full attention,” she said in the statement.

The Globe reports that Driscoll had enlisted expertise from the Liberty Square Group, a local firm headed by former Sen. Edward Kennedy aide Scott Ferson. As she considered a run in recent months, she had also traveled across the Bay State to help survey the playing field.

Democrats still interested in the seat include Newton Mayor Setti Warren, City Year Co-Founder Alan Khazei, and Reps. Mike Capuano and Stephen Lynch. Somerville activist Bob Massie has already declared his intention to run, and former Kennedy Chief of Staff Gerry Kavanaugh is considering a bid.

Roll Call Politics rates this race a Tossup.

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