WASHINGTON — Senator Elizabeth Warren is planning to endorse Hillary Clinton, according to two advisers close to the Massachusetts senator.

Warren is also intrigued by the possibility that she could be picked as Clinton's vice president, but she is not sure that the move would make sense for her, according to the two advisers who spoke on condition of anonymity to discuss her plans freely.

Warren is the only Democratic female senator who hasn't given her nod to Clinton, though she has emerged as a forceful surrogate attacking Republican presumptive nominee Donald Trump in recent weeks. Clinton became the presumptive nominee for the Democratic party this week.