Attorney General Lori Swanson told supporters in an e-mail Sunday that she is running for re-election, ending months of speculation she would run for governor instead.

The third term DFL attorney general had been considered a top contender for her party’s nomination, with a high profile job that made her well known to the state’s voters, and a big list of previous supporters from whom to raise campaign contributions.

“It is an incredible honor to represent our fellow Minnesotans in this office. I appreciate the support of the many people who have encouraged me to run for governor,” she wrote in the e-mail to supporters. “The work of the attorney general’s office is at a critical juncture for the next two months. I must focus all my energy and attention on that work,” she continued, likely referring to a lawsuit against 3M for alleged human health effects of water contamination, scheduled for trial in February.

Swanson’s decision, which other DFL candidates and power brokers waited on for months, upends the DFL race for governor. Most important, the likelihood of an expensive and crowded DFL primary in August is diminished.

A number of high profile DFL candidates had already indicated their intention to run for attorney general, including former Rep. Ryan Winkler, Rep. Debra Hilstrom, former commission of the Department of Commerce Mike Rothman and St. Paul City Attorney Sam Clark.