With just three days of voting left, a fifth union has voted in favor of the tentative $1.6 billion state employee concession package.

The 900-member Connecticut Police and Fire Union, formerly the Protective Services Coalition, voted in favor of the agreement Monday, according to union sources. That brings the total number of bargaining units to vote in favor of the agreement up to 16 with only one bargaining unit, AFSCME Local 749, in opposition.

The four other unions who voted in favor of the agreement include the New England Health Care Employees Union, District 1199/SEIU,  AAUP at the University of Connecticut, Connecticut Association of Prosecutors, and the Connecticut Federation of School Administrators.

The state University Administrative Faculty, AFSCME Local 2836, also voted in favor of the agreement by a hefty margin Monday, according to union sources.

But the vote is far from over and there are a few more hurdles to clear before anyone declares victory.

The vote tallies for the AFSCME locals will become increasingly important since the final SEBAC vote has to clear two separate hurdles. First 14 of the 15 unions must vote in favor of it and 80 percent of the voting members must also approve the deal.

AFSCME, which is the largest of all the state unions with 15,600 members, is the only group that could influence the outcome of the deal, if enough individual members cast a vote against the agreement, it could fail.

Today the AFSCME’s P-2 Human & Social Services unit of roughly 4,200 members votes and on Wednesday and Thursday the last local which belongs to the NP-4 bargaining group of Correction officers will vote. And that will wrap up voting for AFSCME, so it’s possible that tentative results for passage of the overall agreement will be known before the end of the week.

Currently, according to union sources, AFSCME is down less than one thousand votes so the P-2 bargaining unit and Local 391 votes could be critical to its passage.