After weeks of outrage and gridlock, Governor Spitzer, Mayor Bloomberg, and state lawmakers last night were within striking distance of a large-scale compromise that would breathe a little life into the mayor’s congestion pricing plan, somewhat tighten the state’s campaign finance laws, and reward lawmakers with their first pay raise in almost a decade.

By press time, after 72 hours of high-level talks, no deal had been announced, but a Spitzer official said the administration was confident that an agreement would be reached by the end of the night. It’s not likely final approval would come before next week.

Sources familiar with the discussions said Assembly Democrats, the main bloc of opposition to congestion pricing in Albany, were close to agreeing to a deal in which they would authorize the city to begin implementing the infrastructure of the program, such as buying and installing cameras.

The city would not be able to start charging motorists until it received approval from the Legislature, which would vote on the plan next year after a special commission studying the problem of congestion completed its findings.

Led by Speaker Sheldon Silver, Assembly Democrats earlier this week called for a commission but indicated they were opposed to any authorization of congestion pricing. Their tabling of the plan infuriated the mayor, who said lawmakers were harming the health of city residents.

Teaming up with a range of civic and business groups, the mayor has lobbied aggressively for the plan, but was burdened by a late start. He unveiled his proposal in April, giving lawmakers three months to decide on it before time ran out for the state to receive significant seed money from the federal government.

While winning tentative backing from the governor and Senate Republicans, Democrats in the Assembly greeted the plan with skepticism, saying they had many unanswered questions and that voters in districts around Manhattan saw the fees as taxes on the middle class.

A source close to the governor said the administration has been told by federal Department of Transportation officials, who are poised to distribute more than $1 billion in federal grants to cities initiating new anti-traffic programs, that New York would still be in the running for up to $500 million in funds if lawmakers agreed to such a deal.

Under the mayor’s pricing plan, the centerpiece of Mr. Bloomberg’s long-term environmental and infrastructural agenda for the city, a fee of $8 would be imposed on cars driving into and out of Manhattan below 86th Street on weekdays between 6 a.m. and 6 p.m. Trucks would be charged $21. The money would likely help the state and city pay for a long list of mass transit projects. New York would become the first American city to attempt to regulate traffic by charging fees. London started such a program in 2003.

The deal that was being brokered last night was similar to the one floated by the governor in June before negotiations broke down, with Mr. Spitzer and the Republican Senate majority leader, Joseph Bruno, blaming each other for the collapse.

The end of the legislative session was just the starting point in the feud between the governor and the Senate leader.

In the ensuing weeks, Mr. Spitzer questioned Mr. Bruno’s use of state-funded helicopter rides to travel to fund-raisers and Mr. Bruno accused the governor of improperly directing state police to track his whereabouts. The charges triggered multiple investigations in the attorney general’s office and helped create what Albany veterans said was the most poisonous political atmosphere in years.

Despite the acrimony, a complex weaving of interests helped bring warring sides back to the bargaining table. The gridlock reflected poorly on a governor who had promised to bring about major change. Assembly Democrats have grown increasingly impatient for their first pay raise since 1999. The 212 lawmakers make a base salary of $79,500, one of the highest legislative salaries in the nation.

While Mr. Bloomberg had hoped lawmakers would grant the city full authorization for congestion pricing, striking a deal with Assembly Democrats was his best chance for keeping his plan alive.

Mr. Spitzer, however, made a legislative pay raise contingent on Senate Republicans agreeing to a tightening of campaign finance laws.

Therefore, in order for Mr. Bloomberg to get the Assembly to budge on congestion pricing, he needed to persuade Senate Republicans to sign on to campaign finance legislation. Sources said Mr. Bloomberg, whom Republicans are counting on for financial help, was urging Mr. Bruno to swallow a campaign finance bill.

The governor, eager to demonstrate that he’s meeting his campaign pledge of improving Albany’s political culture, has spent months trying to persuade lawmakers to agree to a tightening of New York’s campaign finance laws, whose limits and restrictions on giving are generally looser than most states.

In the spring, the governor sought to reduce contributions limits for statewide candidates to $15,000 from $55,800, lower limits for legislative candidates by about a third, to prohibit political action committees from giving away more than $350,000 a year, and to ban donations from limited liability companies, which have been used by wealthy donors to circumvent limits on individual giving.

Senate Republicans, for whom the ability to raise large sums of political money from a small number of wealthy donors is crucial to their survival in an increasingly Democratic-leaning state, repeatedly rejected the governor’s plan. They claimed the governor was pushing for stricter campaign finance laws to weaken Republicans and drew attention to what they described as the governor’s “hypocritical” practice of rewarding large donors with special access at barbecues and other events.

Sources said Mr. Spitzer agreed to allowing LLC money but with tighter restrictions on establishing multiple donor entities.