Vice President Joe Biden has personally made a series of calls this week to Democratic strategists from Iowa, New Hampshire and South Carolina, asking a final round of detailed questions about how — not whether — to launch a 2016 presidential campaign.

People familiar with the conversations tell CNN that Biden has been making the calls throughout the week, including on Wednesday, just as many leading Democrats argued the window to a potential candidacy was closing in the wake of Hillary Clinton’s strong performance in the party’s first presidential debate. He is asking these people to work for him if he runs.

The vice president has been making clear that his family is fully supportive of him jumping into the 2016 race, according to people familiar with the calls. They are guided by the belief that he has the best chance of keeping the White House in Democratic hands and he could forever regret taking a pass at another shot at the presidency.