WASHINGTON — President Obama is expected today to nominate former Nebraska Sen. Chuck Hagel — a Republican and a Vietnam veteran — for defense secretary.

But Hagel, who would succeed Leon Panetta, is expected to face a fierce confirmation fight because of his stances on Iran and Israel, fellow Republicans said yesterday.

“This is an in-your-face nomination by the president to all of us who are supportive of Israel,” Sen. Lindsey Graham (R-SC) told CNN’s “State of the Union.”

Hagel voted against going to war with Iraq, and once said “the Jewish lobby” intimidates the Senate on Israel.