Battalions of pro-Israel advocates marched up to Capitol Hill on Tuesday in a vigorous lobbying campaign to win support for tighter sanctions against Iran, relief for Israel aid from automatic spending cuts, and a new designation of the Jewish state as a “major strategic ally,” a status that would help insulate Israel from any further aid cuts.

Wrapping up the annual policy conference of the American Israel Public Affairs Committee, or AIPAC, more than 13,000 members of the powerful Israel lobby from all over the United States visited the offices of all members of the House and Senate — an indication of the bipartisan reach and influence of the group in both chambers.

At the top of their agenda is convincing lawmakers to support a new Iran bill (HR 850) from House Foreign Affairs Chairman Ed Royce, R-Calif., and supported by ranking Democrat Eliot L. Engel of New York that would extend existing sanctions targeting Iran’s energy and financial transactions to include an even broader range of its commerce with the rest of the world. Several senators are working on a measure that is expected to be even more expansive.

The grass-roots lobbyists also asked lawmakers to find some way to shield the $3.1 billion in annual U.S. aid to Israel from the automatic across-the-board spending cuts that took effect on March 1. Under the sequester, Israel stands to lose $155 million. Israel is the largest recipient of U.S. foreign aid.

“We believe Congress might be able to find a way to walk around the sequester with the foreign aid package,” said Rabbi Jonathan Miller of Birmingham, Ala., who was lobbying members of his state’s congressional delegation.

An AIPAC official said the lobby was not seeking an exemption for the Israel aid. “We are saying that an alternative should be found to sequestration because it is bad policy. We believe it is essential for American and Israel security interests that the assistance be maintained and not reduced.”

The lobbyists were expected to face the most resistance from tea-party-backed Republicans, who support the sequester as a way to start reducing government spending.

AIPAC lobbyists said they also were asking lawmakers to back a proposal that would designate Israel a “major strategic ally” of the United States — a relationship that no other nation enjoys. The new designation would mean closer cooperation between the United States and Israel on missile defense, military technology and homeland security. AIPAC is seeking the designation as a way to protect the current level of Israel aid from budget cutters.

Lawmakers expressed strong support for Israel but said it was too early to say if they could insulate Israel aid from the sequester cuts.

“We’ll do everything that we can to make sure that Israel has the qualitative military edge,” said Florida Republican Ileana Ros-Lehtinen, chairwoman of the House Foreign Affairs Subcommittee on the Middle East and North Africa and an outspoken supporter of Israel. “This week, we’re going to do the CR to put back some money that will suffer as a result of the sequester. So it’s in the early stages. We’re going to see how everything shakes out.”

She was referring to the House proposal (HR 933) for a continuing resolution that would fund the government until the end of the fiscal year on Sept. 30. Unveiled Monday, the legislation includes new appropriations for the Pentagon, military construction and veterans affairs, while maintaining fiscal 2012 funding levels for the rest of the government.

The proposed appropriation for the Pentagon includes nearly $500 million for joint U.S.-Israeli missile defense programs, including the Iron Dome system, which successfully intercepted some 80 percent of short-range missiles fired at Israel by Hamas fighters in the Gaza Strip during a round of fighting in November.

But California Democrat Brad Sherman, a senior member of the House Foreign Affairs Committee, cautioned against seeking any broader exemption from the sequester for Israel aid.

“An exemption for Israel would raise questions,” he said. “If there’s one exemption, what other exemptions will there be?”

In the Senate last week, New Jersey Democrat Robert Menendez, chairman of the Foreign Relations Committee, and South Carolina Republican Lindsey Graham, one of the party’s leading voices on defense, introduced a nonbinding Iran resolution in advance of the AIPAC lobbying effort. The measure “urges” the United States to provide Israel with military, diplomatic and economic support if it is “compelled to take military action in self-defense” against Iran.