Call it the Cornhusker question mark.

Word leaked Monday that former Sen. Bob Kerrey (D) is strongly reconsidering a comeback Senate bid in Nebraska, eliciting a mixture of reactions from Capitol Hill to Lincoln about a decision that could take a sure pickup off the table for Republicans.

Regardless of what Kerrey decides to do, the GOP is expected to win the seat of retiring Sen. Ben Nelson (D) at this point. But Kerrey, a well-liked former governor and Senator, would put the state in play and force Republicans to spend resources there. Kerrey is considered the only Democratic candidate who can make the race competitive, despite having lived in New York City for the past 11 years. 

“It’s definitely a game-changer,” Democratic strategist Ed Espinoza said.

Democrats went to great lengths to recruit Kerrey. Knowledgeable Democratic sources said Senate Majority Leader Harry Reid (D-Nev.) and Democratic Senatorial Campaign Committee Executive Director Guy Cecil have been instrumental in wooing Kerrey.

Sources said Reid may try to convince Democratic Conference members to allow Kerrey to re-enter the Senate with his seniority intact if he wins.

In addition to that incentive, one Democratic operative said Kerrey might view a 2012 Senate bid more favorably than he did in January because of signs that the economy is improving, possibly reducing the difficulty of running as a Democrat in Nebraska in a presidential year.

But Kerrey was still considering late Monday and had yet to make up his mind, and Democrats who have followed his career pre- and post-Senate retirement said the situation is fluid and remains delicate. These sources worried that the leak of news that Kerrey is reconsidering his decision not to run could scare him off and keep him in New York, where the 68-year-old has lived since 2001.

The Washington Post first reported the news Monday that Kerrey was running for Senate. Throughout the day, reports conflicted over whether Kerrey had made a definitive decision.

Ever since Kerrey announced he would not run for Senate on Feb. 7, Nebraska had faded away from relevance in the big picture chess game that is the Senate playing field. Interest in the race had shifted from the general election to the primary, as the growing consensus was that Republicans would take the seat and the party’s nominee would be the state’s next Senator.

Many Nebraska Democrats were caught surprised and flat-footed when reached for comment Monday. The state party and the DSCC essentially went on lockdown and weren’t responding on the record to press inquiries, which only added to the conflicting reports.

DSCC Chairwoman Patty Murray (Wash.) declined to comment Monday evening on the reports about Kerrey. Murray also would not confirm possible conversations with Kerrey, but she did allude to the conventional wisdom that the Nebraska seat will be difficult for Democrats to hold.

“Bob Kerrey will be a great candidate there, if he decides to run,” Murray said.

At the same time, Kerrey was mocked on Twitter for playing Hamlet. And some Democrats privately expressed their displeasure with the ill-timed leak.

“True or not true, the leak is frustrating and damaging because it takes the control of the message away from the candidate,” a Democratic consultant told Roll Call. “Apparently, we have a bunch of bozos masquerading as political operatives in D.C. You wonder if they actually wear their clown makeup to the office.”

Republicans remain confident, even cocky, that they will defeat Kerrey if he runs.

“Bob Kerrey isn’t just far more liberal than many of his friends in Washington — he also has far more serious electability problems than Ben Nelson ever did,” National Republican Senatorial Committee Executive Director Rob Jesmer wrote in an open memo.

But Kerrey has a brand in the Cornhusker State that Democrats are touting.

“He makes the race competitive in a unique way if he decides to run,” said a Democrat familiar with Nebraska politics.

But Republicans are quick to note two biographical points: Kerrey’s New York City residence and that the last time he was on a Nebraska ballot was in 1994.

Republicans say Nebraska is not the same state as when Kerrey left. They also say he is not the same man.

Kerrey considered a run for New York mayor in 2005, and his time in New York was spent as president of the New School, located in liberal Greenwich Village.

In his previous stretch of consideration in January, both he and Democrats emphasized his family and business ties that remain in Nebraska.

Not all Democrats are pushing for a Kerrey run. 

“I do not believe the report that Bob Kerrey is getting in the Senate race,” Democratic Senate candidate Chuck Hassebrook wrote in a statement. “He told me as recently as a few days ago that he would assist my campaign. I gave up my seat on the University of Nebraska Board of Regents based on his word. I do not believe he would go back on it.”

The Republican field is set, with the competitive primary slated for May 15.

The frontrunner is Attorney General Jon Bruning. He is well-funded and has establishment backing in the state.

That said, he has had campaign stumbles and ongoing queries into conflicts of interest during his tenure as attorney general. Also running are state Treasurer Don Stenberg and state Sen. Deb Fischer.

Late Monday, Nelson said he hasn’t talked to Kerrey recently and that he put his money on Democrats holding the seat.

“There are two more days left for someone else to file, but I think whoever wins that primary on the Democratic side still has a great chance to win the general election,” Nelson said. “The other field is weak, very, very weak.”

Niels Lesniewski and Humberto Sanchez contributed to this report.