WRAPUP 1-U.S. House heads toward close healthcare vote

* Pelosi confident on winning House vote

* House budget panel takes first step toward passage

* Democrats still await final bill, cost estimates

By John Whitesides and Donna Smith

WASHINGTON, March 15 (Reuters) - Congressional Democrats took the first step on Monday toward a quick final vote on a healthcare overhaul, and U.S. House of Representatives Speaker Nancy Pelosi vowed to muster the votes needed to pass it.

With a close vote expected later this week, House Democrats hustled to line up support and President Barack Obama hit the road in Ohio to push his case for a sweeping overhaul of the $2.5 trillion healthcare system.

Republican opponents promised to make Democrats who support the healthcare overhaul pay for their stance in November's congressional elections, when Democratic control of Congress could be threatened by political fallout over the issue.

But Democratic leaders counseled nervous lawmakers to hold firm and pass the bill, which has been the focus of a political battle that has mired the U.S. Congress in legislative gridlock for nine months.

"We need courage," Obama told a crowd in Strongsville, Ohio, during his third road trip in the past week to rally support for his top legislative priority. "This debate is about far more than politics."

The House Budget Committee launched the push toward a final vote, advancing changes to the Senate-passed healthcare bill sought by House Democrats and Obama.

Democrats Chet Edwards and Allen Boyd, who opposed the House-passed healthcare bill in November, broke with their party on the largely party-line 22-16 vote.

House Democratic vote-counters say they are still short of the 216 votes necessary to pass the overhaul but Pelosi was confident they will hit the magic number by week's end.

"When we bring the bill to the floor, we will have the votes," Pelosi told reporters.

The overhaul would constitute the most dramatic changes to the healthcare system in more than four decades, extending coverage to more than 30 million uninsured Americans and banning insurance practices like refusing coverage to those with pre-existing medical conditions.

Health insurer shares were mixed on Monday as the broader market was little changed. The Morgan Stanley Healthcare Payor index .HMO was up 0.2 percent and the S&P Managed Health Care index .GSPHMO dropped 1.1 percent.

'WE'RE GOING TO MAKE THIS HAPPEN'

Obama also maintained the upbeat tone put forth by the White House during the weekend, telling ABC News: "I believe we are going to get the votes. We're going to make this happen."

Republicans condemn the health bill as a costly government takeover that would lead to higher insurance premiums and less consumer choice. They plan to launch a series of television ads against House Democrats who support the overhaul.

"All we hear about is the arm-twisting and the horse-trading that's going on over there behind the scenes -- the mad dash ahead of the big vote," Senate Republican leader Mitch McConnell said. "And once again, Americans can't believe what they're hearing."

Democrats are waiting for final cost estimates from the Congressional Budget Office and more advice from the Senate parliamentarian before unveiling a final healthcare package and deciding the exact process for passing it.

In a two-step process, House Democrats want to approve the Senate's version of the bill and make changes sought by Obama and House Democrats through a separate measure passed under budget reconciliation rules.

Those rules require only a simple majority in the 100-member Senate, bypassing the need for 60 votes to overcome Republican procedural hurdles.

Pelosi said there were no decisions on whether the House would require a direct vote on the Senate bill or include it in a vote on the reconciliation package. "When we have the substance then we will decide on the process," she said.

The changes in the reconciliation bill include expanding subsidies to make insurance more affordable and extending more state aid for the Medicaid program for the poor.

They also would eliminate a controversial Senate deal exempting Nebraska from paying for Medicaid expansion costs, close a "doughnut hole" in prescription drug coverage for seniors and water down a tax on high-cost insurance plans.

Republicans want Democrats to vote directly on the Senate bill, which includes unpopular provisions like the Nebraska Medicaid deal, so they can use the vote against them in November.

"Process is substance," Representative David Dreier, the senior Republican on the House Rules Committee, told reporters. "To resort to these kinds of tactics to deal with this is just plain wrong."

(Additional reporting by Tabassum Zakaria and Thomas Ferraro; editing by David Alexander and Bill Trott)