Guess it’s never too soon: Hillary Clinton might not announce her 2016 presidential candidacy until April, according to Politico’s Mike Allen, but some within her sphere are already floating vice presidential possibilities.

Allen canvassed the emerging Clinton infrastructure, with Robby Mook as presumed campaign manager, John Podesta as likely campaign chairman and long-time Clinton advisers like Cheryl Mills, Philippe Reines and Huma Abedin in prominent roles either inside or outside the campaign. And President Bill Clinton is already “deeply engaged,” per Politico.

But beyond the bureaucracy, Allen surfaced some of the vice presidential possibilities being discussed by anonymous sources somewhere within Clinton’s world.

Sens. Tim Kaine (D-VA) and Michael Bennet (D-CO) were portrayed as early frontrunners. Sen. Cory Booker (D-NJ), Housing and Urban Development Secretary Julian Castro, Labor Secretary Tom Perez and California Attorney General Kamala Harris were also name-checked.

At this stage, it’s hard to know how seriously to take that list. And Clinton advisers assured Allen that they didn’t want to get ahead of themselves and invite another inevitability backlash. But if nothing else, it appears some of them can’t help thinking ahead.