HARRISBURG - Gov. Rendell met behind closed doors yesterday with House and Senate Democrats to drum up support within his party for his plan to raise Pennsylvania's income-tax rate by 16 percent.

Democratic leaders later lined up to support the idea, calling it the only option in these dire economic times for a balanced budget other than slashing government programs.

But while leaders backed the tax hike, it remained unclear whether rank-and-file Democrats did. Republicans said they would oppose it.

"This tax increase is modest. We picked a tax which is the least oppressive of any Pennsylvania taxes," Rendell said at a news conference, repeating the pitch he had made to legislators: "It's the right thing to do."

Last week, Rendell proposed raising the state's income-tax rate from 3.07 percent to 3.57 percent for three years to help close a growing budget shortfall projected to reach $3.2 billion. The new fiscal year begins July 1, and lawmakers are under pressure to enact a new spending plan by then.

Senate Minority Leader Robert J. Mellow acknowledged that the chances of an increase passing this year are made tougher because many lawmakers are coming off elections in which they vowed not to support such hikes.

"For those people who say they will never vote for a tax increase, the things that are growing on the trees out there right now are leaves, not dollar bills," said Mellow (D., Lackawanna). "We can only make them available by going to the taxpayers."

At the news conference, House Appropriations Chairman Dwight Evans (D., Phila.) refused several times to say how many House Democrats he believed supported the tax hike after the governor made his sales pitch.

"It's a process. . . . We are going to keep working on it until we have" the required votes, said Evans, who was among the first to suggest a tax increase was a necessity.

Meanwhile, Rep. Ron Buxton (D., Dauphin) plans to introduce a bill today that would allow the government to continue operating under a so-called stopgap budget until July 30.

Rendell and Senate Majority Leader Dominic Pileggi (R., Delaware) last week said they would consider such a measure as a way to pay salaries beyond July 17, when the government loses its authority to issue its first paychecks in the new fiscal year.

But the idea clearly didn't go over well with Democratic leaders at a news conference yesterday.

"It doesn't work," Mellow said of stopgap measures. "It's merely a delay tactic."

In another budget matter, Rendell is expected to make public, as early as today, an additional $500 million in government-program reductions. Agency secretaries reviewed Rendell's suggestions for cuts over the weekend and were expected to return their final recommendations to the governor last night, said Rendell's spokesman, Chuck Ardo.

Contact staff writer Mario F. Cattabiani at 717-787-5990 or mcattabiani@phillynews.com.