CORRECTED - UPDATE 1-Obama urges end to finger-pointing on budget

* Obama says criticism should be constructive

* Republicans say budget costs too much

* Some Democrats also upset with plan (Corrects size of projected deficit this year and adds next year's projected deficit in paragraph 6) (Adds details and quotes)

By Matt Spetalnick

WASHINGTON, March 17 (Reuters) - President Barack Obama, stepping up lobbying for his record $3.5 trillion budget, called on Tuesday for an end to finger-pointing and challenged Congress to offer constructive changes.

"With the magnitude of the challenges we face right now, what we need in Washington are not more political tactics, we need more good ideas," he said after a White House meeting with fiscally-conservative Democratic lawmakers who have voiced concern about deficit spending.

"We don't need more point scoring, we need more problem solving," he told reporters.

Obama's intensified effort to sell his budget came as Republicans complained that his proposed record spending, much of it aimed at lifting the U.S. economy out of deep recession, costs too much.

Some of Obama's own Democrats, who expanded their hold on Congress in the November election that brought him to power, are also upset with provisions on farm subsidies, tax deductions, industrial emissions and some other items.

The budget proposal Obama put forward last month, which projects deficits of $1.75 trillion this fiscal year and $1.17 trillion next fiscal year, lays out ambitious plans to expand healthcare, upgrade education, move the United States toward energy independence and combat global warming.

Nearly two months after taking office, Obama is also trying to distance his economic and budget plans from mounting public anger over costly government bailouts.

He assured Americans on Monday he shared their outrage over hefty bonuses paid to executives of AIG, a giant insurer receiving up to $180 billion in federal rescue aid, and would try to yank back the rewards.

Mindful of political maneuvering as the budget battle heats up, Obama said, "If there are members of Congress that object to specific policies and proposals in the budget, then I ask them to propose constructive alternative solutions."

"'Just say no' is the right advice to give your teenagers about drugs. It is not an acceptable response to whatever economic policy is proposed by the other parties," he said.

Obama took office vowing a new era of bipartisan cooperation but has had a hard time making good on his promise as the political realities of Washington have prevailed.

"The American people sent us here to get things done," Obama said. "Let's pass a budget that puts this nation on the road to lasting prosperity." (Additional reporting by John Whitesides and David Alexander; Editing by Bill Trott and Alan Elsner)