Aides to former Vice President Joseph R. Biden Jr. are discussing the possibility of seeking an alliance with Senator Amy Klobuchar in next week’s Iowa caucuses, a plan that would involve a pledge to help each other in precincts where one of them does not have enough support to win delegates.
Three staff members for Mr. Biden’s Iowa campaign tentatively floated the idea to a top Klobuchar adviser at a meeting this week, according to Democrats briefed on the meeting.
People in both the Biden and Klobuchar camps played down the discussion, which took place at a Des Moines restaurant, and aides for Ms. Klobuchar said they did not regard it as a serious overture. But there is little doubt among Mr. Biden’s allies in the state that his campaign is contemplating such steps, with an eye toward preventing a messy split among moderate candidates on Monday.
The Biden officials, led by the campaign’s Iowa director, Jake Braun, asked the Klobuchar strategist, Pete Giangreco, about the prospect that the two campaigns could encourage their supporters in the state to back the other candidate in precincts where Mr. Biden or Ms. Klobuchar fall short of the 15 percent threshold required to reach the second round of balloting.
Mr. Giangreco, however, said Ms. Klobuchar was not interested in any such agreement at the moment, according to the Democrats familiar with the meeting, who spoke on the condition of anonymity to discuss a private conversation.
Ms. Klobuchar’s campaign reaffirmed its lack of interest in an alliance of any kind on Tuesday evening. Tim Hogan, Ms. Klobuchar’s communications director, expressed confidence in her trajectory in the state.
“Our campaign is on the rise,” Mr. Hogan said. “We’ve never made caucus deals with other campaigns and don’t intend to.”
Mr. Biden’s campaign declined to comment on Tuesday night. It was not immediately clear if Mr. Braun was acting on instructions from more senior Biden aides or if he was acting on his own.
But the conversation illustrates the urgency Mr. Biden’s campaign is feeling as polls show him dividing votes with the other moderate candidates in the race, and Senator Bernie Sanders taking a lead going into Monday’s caucuses.
For weeks, supporters of Mr. Biden have expressed hope that they can win Iowa if the bulk of Ms. Klobuchar’s supporters migrate to him on the second ballot. In an interview Sunday, former Gov. Tom Vilsack of Iowa, a top Biden supporter, made the case for why those supporters should rally to Mr. Biden, and even suggested Ms. Klobuchar might be considered as his running mate. She has gained strength in Iowa, but is still polling below 15 percent in most state polls.
The dinner suggests Mr. Biden’s camp knows that movement from her backers may not happen without Ms. Klobuchar’s blessing. In addition to Mr. Braun, two other Biden aides in Iowa, Bill Doerrer and Claudia Chavez, attended. The four political operatives know one another from their roots in Chicago politics.
It is not unusual for Democratic campaigns in Iowa to form alliances before the caucuses. In 2004, for example, John Edwards and Dennis Kucinich agreed to encourage their supporters to join forces behind whichever of the two had more strength in a given precinct. It helped Mr. Edwards, but not enough to defeat John Kerry, who won the caucuses that year.
One complication for Mr. Biden and Ms. Klobuchar is that they are not the only candidates vying for the support of moderate Iowa Democrats. Pete Buttigieg and Senator Elizabeth Warren are also polling in the teens there and could ensure that none of the four leading alternatives to Mr. Sanders can coalesce support.
So there may be more flirtations in the days leading up to the caucuses, as the campaigns seek an advantage in Iowa’s complex system. But many political veterans in the state believe that in an era when voters are increasingly well-informed, it will be difficult to move them en masse to another candidate, even if their preferred choice asks them to do so.