A series of speeches he's scheduled to deliver during the next few weeks to Democratic groups in the Indianapolis suburbs and southern part of the state might help him choose.
Donnelly, D-Granger, began Monday by speaking at the Hamilton County Democratic Party's Jefferson-Jackson Day Dinner. He's also scheduled to speak at dinners in Dearborn, Floyd, Franklin and Hendricks counties, as well as the 3rd Congressional District dinner in Columbia City, according to his office.
He talked Monday about his focus on issues important to working-class families and his willingness to do what he feels is right, even when it's not immediately popular. That was the case, he said, when he voted for federal plans to rescue the financial sector in 2008 and the auto industry in 2009.
"I've always taken the attitude that I'm the hired help," Donnelly told the audience.
"I have been privileged that some of the folks in this state have asked me to take a look at running for the United States Senate," he said. "I'm doing that now. I'm not running to be somebody for Wall Street; I'm running to be somebody for you."
Sen. Richard Lugar, a Republican, is running for re-election to a seventh term, but he'll face a challenge from Indiana Treasurer Richard Mourdock in the 2012 primary. Donnelly has said he's leaning strongly toward a Senate bid if the Indiana General Assembly redraws the 2nd District this year to favor a GOP candidate.
Donnelly said county chairs around the state have asked him to speak at their groups' Jefferson-Jackson Day Dinners. "This is part of an obligation of giving back to the party," he said, "but, at the same time, it's also a chance to talk to people about a possible Senate run."
Elizabeth Bennion, a political science professor at Indiana University South Bend, said these interactions with the party's base are important.
"Even if Donnelly is the only candidate on the primary ballot, he will need Democrats to make donations, knock on doors, make phone calls, encourage their friends to vote, and go to the polls on Election Day," she said. "Building a base of local supporters in communities across the state is an important part of any statewide election campaign. This is particular if one is not the incumbent and cannot rely on statewide name recognition and funding advantages."
Coincidentally, Donnelly began this speaking series in the state's most-Republican county. He said that's not part of any plan, but Bennion said it still makes a statement.
"Accepting a speaking invitation in Hamilton County sends the signal that Donnelly, if elected, will represent all Hoosiers, not just those who live in Democratic strongholds," she said.
Indiana Republican Party spokesman Pete Seat said of Donnelly: "He can spend all the time he wants buttering up the party faithful, but the fact is once Hoosiers around the state hear about Donnelly’s support of tax increases and the ObamaCare monstrosity, any potential candidacy will be met with a giant thud."