Senate committee holds hearing on Biden's ambassador nominee amid GOP concerns over Iran policy

Jack Lew, former Treasury Secretary under Obama, nominated by Biden for ambassador to Israel.
Republicans criticize Lew's role in 2015 Iran nuclear deal negotiations.
Senate Democrats aim for quick confirmation citing Lew's experience.
Biden visiting Israel to show support amid tensions with Hamas.
White House weighing $90-100 billion funding request for Israel, Ukraine, Taiwan.