Obama aides are keeping the hunt for a running mate a closely guarded effort. Obama has not shared his thinking on how much weight he will give to calls from some Democrats to make Clinton the vice presidential nominee.

Other potential choices include Richardson and former Sen. John Edwards of North Carolina. Both ran against Obama for the nomination but later dropped out and endorsed him.

Others who may be on Obama’s list include Gov Kathleen Sebelius of Kansas and three senators: Joseph R. Biden of Delaware, who also ran for president this year; Claire McCaskill of Missouri; and Jim Webb of Virginia.

At a visit to a Boca Raton synagogue Thursday, Obama got a question, posed a bit indirectly, about whether he would name Clinton as his vice president.

“Will you be willing to consider everyone a possible running mate, even if his or her spouse is a pain in the butt?” one person asked.

After he and the crowd stopped laughing, Obama cautioned it was too soon to talk about possible vice presidential nominees. “Two weeks from now, we will know who the Democratic nominee is going to be, so I don’t want to jump the gun,” he said.

But he noted that one of his heroes, Abraham Lincoln, stocked his administration with rivals, and he said he would be willing to do the same.

In his visit to Florida, Obama has been trying to address weaknesses that emerged in the course of his campaign fight with Clinton. One point of concern is Jewish voters. On Thursday, he spoke to Jewish voters and sought to address any misgivings. At the Boca Raton synagogue, B’nai Torah, Obama was introduced by three Jewish elected officials from Florida, who assured the crowd that Obama was a friend to Israel.