The former GOP congressman is said to weigh a presidential run.
It's the latest sign the conservative favorite might run in 2016.
The former president said the U.S. isn't in "danger" and called for more answers.
More than 300 former Obama campaign staffers are urging Warren to run.
Clinton is discussing the details of how to launch a likely bid.
Sanders will meet with progressive groups in the state.
"It is a test of an individual’s resolve," the Texas governor said.
The potential 2016 contender will meet Prime Minister Netanyahu.
He is moving to Clinton's left on the issue.
The dealings raise questions about a presidential campaign.