Boccieri, who had voted against the healthcare bill before the House in November, said Friday morning that he would now support the healthcare measure set for a vote on Sunday.

"There's too many politicians worried about their future," Boccieri said, adding that too many leaders are worried about keeping control of the House. Boccieri appeared on the Capitol surrounded by Ohio constituents.

House Speaker Nancy Pelosi (D-Calif.) and other Democratic leaders have been working to ensure they'll have the votes to proceed with a healthcare package during a highly anticipated Sunday vote. 

"Yes, I will be voting yes for the bill," Boccieri said, adding that a score on the bill's budget impact was key to switching his vote. "I was very encouraged by the budget results that came back from the Congressional Budget Office."

Since the Congressional Budget Office (CBO) announced its score of the healthcare package, which uses the Senate-passed health bill as its base but makes changes to it, a steady trickle of lawmakers have officially announced how they would vote for the package.

The magic number for Democrats is 216, meaning that they are all but assured passage of their healthcare bill if they can secure that number of votes.

"I feel very sure that we'll vote sometime after 2 o'clock on Sunday, and the bill will pass," House Majority Whip James Clyburn (D-S.C.), the Democrats' chief vote-counter, said Thursday following a closed-door caucus meeting.