AMMAN, Jordan | With its Friday anti-government rallies here attracting more protesters each week, the Muslim Brotherhood has positioned itself to become a leading player among Jordanian lawmakers if democratic reforms are enacted.

The Islamic Action Front (IAF), the political wing of the Muslim Brotherhood, is Jordan’s only established opposition party, and analysts estimate that it could win up to 25 percent of parliamentary seats if electoral reforms are carried out.

Although the Brotherhood’s domestic agenda contains uncontroversial goals such as fighting corruption and poverty, some Jordanians worry that the Islamist group’s hard line against Israel could upset the region’s delicate security balance.

Political analysts say the IAF, which has participated in many of the reformist rallies that have taken place here every Friday for the past two months, has no practical reason to seek to dissolve Jordan’s tenuous peace deal with Israel, the key U.S. ally in the Middle East.

But IAF Deputy Secretary-General Nimer al-Assaf has uttered strong words against the Jewish state. “We do not agree to the peace treaty with Israel simply because we do not feel that it is just,” he said.

Jordan’s King Abdullah II, in an image made available by the Jordanian Royal Court, waves to crowds who throng the streets of Mazar Shamali, 80 miles north of Amman, to greet the monarch on Tuesday. The king appears to be almost universally popular in Jordan. (Associated Press)

Mr. al-Assaf accused Israel of having imperialistic aims in Jordan, but he said the future of the peace agreement should be decided by a popular referendum.

When it was founded in the 1920s, the Muslim Brotherhood endorsed the violent spread of fundamentalist Islam, but it has since abandoned support for terrorism, except against Israel.

Jordanian analysts say the IAF is neither prepared to take on Israel and the international status quo nor capable of maintaining popular support if the organization diverges from addressing domestic concerns.

Jordanians face widespread poverty and almost 14 percent unemployment. Taxes range from 16 percent on medicines to as much as 40 percent on gas. In the heart of the Middle East, Jordanians complain that they pay more at the pump than Americans.

Meanwhile, salaries have stagnated as prices rise. Average working people are earning about $350 a month here in the capital, Amman, largely considered to be the most expensive city in the Middle East.

Mohammad al-Momani, a political science professor at Yarmouk University in Irbid, Jordan, said the IAF may oppose policies that support Israel, but the group is unlikely to try to derail the region’s security balance.

“They know this is very controversial,” he said. “They know this is one of the things that tends to be very sensitive to the national interests of the state, so they are staying out of it.”

Hassan A. Barari, a political science professor at the University of Jordan, said the IAF also will be forced to compete with other political organizations if electoral reforms are carried out.

“They will shelve their ideology in this case because they want to be responsive to the needs of the people,” Mr. Barari said. “They want to be seen as someone who can deliver. If they stick to their ideological rhetoric, they will do nothing.”

Some secular activists in Amman also fear that the IAF is using the unrest for political gain and accuse the Brotherhood of aiming to impose a radical Islamic agenda on Jordanians.

IAF officials say their goal is to participate in public life in cooperation with secular groups, not to impose a religious or political agenda on the rest of the country.

“Our party believes in sharing,” Mr. al-Assaf said. “And the problems in Jordan are so enormous that it needs the effort of everybody in Jordan to come together to carry out those reforms.”

Many Jordanians, including the IAF, would like election laws that make parliament more representative of the population. Current laws, they say, are based on geographical boundaries that leave Palestinians — roughly half the country’s population — underrepresented.

Yet many Jordanians, even some reformists, fear that a more dominant political role for Palestinians would threaten their fragile peace with Israel and their national identity.

The idea becomes even more controversial when taken a step further. The IAF and other opposition groups have called for the popular election of the government and a transition into a constitutional monarchy. The prime minister and the Cabinet currently are appointed by the king, who appears to be almost universally popular in Jordan.

Most Jordanians say King Abdullah II is a progressive reformist who seeks to improve the lives of the people. They blame his government for the corruption and bad laws that have squeezed the nation’s poor in recent years.

Mr. Barari says the people may love their king but will not sit still if reforms are not enacted soon. What are now peaceful, carefully orchestrated Friday protests, he said, easily could dissolve into more urgent and more radical calls for change.

“If the process fails to improve the lives of the people,” he said, “Jordanians will go back to the streets.”

On the streets of Amman, pro-monarchy signs are common, and locals readily sing praises of the king. Though their devotion to the Western-educated leader appears to be genuine, it is illegal in Jordan to criticize the king, leaving him largely above reproach.

The queen, however, is increasingly under fire. Last month, tribal leaders issued a statement accusing Queen Raina of corruption, insensitivity and claiming public lands for her family. Leaders also warned the king that reform must come soon and called for the direct election of a new government, according to the New York Times.

“We are on the path where the floods of Tunisia and Egypt will reach Jordan sooner or later, whether we want it or not,” the statement says.

King Abdullah has said he stands with the protesters for reform, democracy and economic justice. In a move to pre-empt unrest, the king dismissed his Cabinet last month and appointed a new prime minister.

On Monday, the king spoke about election reform and called for a national consensus to take an “irreversible step towards building a bright future that the Jordanian people deserve,” according to the Jordan Times, a government news source.