Washington ? President Barack Obama plunges into a difficult test of his leadership this week, struggling to get a divided Congress to agree on his economic recovery package while pitching a new plan to ease loans to consumers and businesses.

The Senate’s $827 billion stimulus legislation seems assured narrow passage by Tuesday. Harder work for Obama and the Democrats comes in the days ahead, when the House and Senate attempt to reconcile differences in their two versions.

Obama and Democratic Party leaders had hoped to have a bill ready for the president’s signature by Feb. 16 — a deadline that grows more challenging by the day.

At the Treasury Department, Secretary Timothy Geithner delayed the unveiling of a new bailout framework for financial institutions from today to Tuesday to let the administration focus on the Senate legislation.

Geithner is considering steps to broaden the use of a new lending facility at the Federal Reserve, provide government guarantees to help banks deal with their troubled assets, and continue direct infusion of capital into banks in exchange for securities and tougher accountability rules.

For Obama, the economy has become a two-front engagement, with one effort aimed at creating or saving jobs and the other at unfreezing the credit markets. Amid the urgency created by nearly 600,000 new unemployed workers last month and new bank failures, Obama’s economic prescriptions are coming under critical scrutiny by both Congress and the American public.

The House and Senate bills are about $7 billion apart in cost and overlap in numerous ways. But the Senate bill has a greater emphasis on tax cuts, while the House bill devotes more money to states, local governments and schools.

Lawrence Summers, Obama’s top economic adviser, signaled the struggle ahead as he made the rounds of Sunday morning talk shows. “There are crucial areas, support for higher education, that are things that are in the House bill that are very, very important to the president,” he said on ABC.

Rep. Barney Frank of Massachusetts, the Democratic chairman of the House Financial Services Committee, warned that reductions in state spending in the Senate bill would hurt local communities.

“To get any Republicans at all, you had to adopt a cut that’s going to mean policemen and firemen are going to be laid off,” he said.

Sen. John Ensign of Nevada, a member of the Senate Republican leadership, dismissed Frank’s complaint as “fear-mongering.”

The Senate bill is finely tuned. With only two or three Republicans on board, it is guaranteed, at most, 61 votes; the bill needs 60 votes to advance and avoid procedural hurdles. Any change in the balance struck by the Senate bill could doom it.

Sen. John McCain, R-Ariz., a vocal critic of the stimulus bill, complained that Republicans won’t be involved in the final negotiations. “That’s the way the Bush administration, when we Republicans were in charge — that’s the way we did business,” he said. “But I thought we were going to have change.”

Obama will take his case to the American people at 7 p.m. tonight with his first prime-time news conference. He’ll also participate in town hall-style meetings in cities suffering particularly hard times — Elkhart, Ind., today and Fort Myers, Fla., on Tuesday.