Speaker Nancy Pelosi (D-Calif.) says Democrats have enough votes to push healthcare reform through the House.

Both moderate and liberal Democrats have begun defecting, leaving Pelosi scrambling to put together the 216 votes necessary for final passage. But the speaker dismissed concerns that her coalition was falling apart.

"We're very excited about where we are and will not be deterred by estimates that have no basis in fact," she said at a post office dedication in San Francisco, according to the Associated Press.

The House is counting on the Senate to pass additional legislation to modify healthcare reform after it's passed into law. Several House lawmakers have expressed skepticism that they can trust the Senate to come through on that pledge.

Pelosi wouldn't say when she expects the House to vote.