Fernández Rundle convened a grand jury last year that reviewed policies for voting by mail and recommended that the elections department step up its security for online requests. County commissioners are scheduled to vote Tuesday on a resolution sponsored by Commissioner Esteban “Steve” Bovo directing administrators to implement the recommendation.

Friday’s searches raised the specter of another crime in the already scandal-plagued election for Congressional District 26, which extends from Kendall to Key West.

The Miami Herald found that the first batch of requests, which originated from at least two Miami-area IP addresses last July, targeted Miami-Dade Democratic voters in the congressional district where Garcia was running in the primary against Gustavo Marin, Gloria Romero Roses and Justin Lamar Sternad. Later batches using foreign IP addresses targeted Republican voters in the two Florida House districts.

Garcia won the primary and later defeated incumbent Republican David Rivera in the general election.

Though Garcia bested Rivera by about 11 percentage points, and Democratic President Barack Obama won the district by about seven points, Republicans still view Garcia as vulnerable. Three GOP challengers have already announced plans to run against him in 2014.

One of them, Miami-Dade School Board member Carlos Curbelo, pounced on Friday’s news.

“Joe Garcia has to come clean immediately and tell the public if his campaign is involved in absentee ballot fraud,” Curbelo said in a written statement.

Last year’s tumultuous primary resulted in a separate, federal corruption investigation into whether Rivera had ties to Sternad’s illegally funded primary campaign. Rivera has denied any wrongdoing.

Congressman Garcia said he will hire Coral Gables attorney William Barzee, a longtime campaign contributor, to investigate the phantom-ballot scheme internally and cooperate with prosecutors.

As communications director, Sopo received a salary of $12,744 between Jan. 17 and March 31, Garcia’s congressional office records show. He was not paid by Garcia’s campaign last year, though his company, GS Strategies, received $33,450 in 2010 when Garcia lost his congressional bid to Rivera. Sopo also worked on Garcia’s failed 2008 campaign against Republican U.S. Rep. Mario Diaz-Balart.

In 2012, Garcia’s campaign paid Estes $44,395 through his company, Estes Consulting. Between 2010 and 2011, he was paid $5,770 by the Florida Democratic Party.

A woman who would not give her name but identified herself as Estes’ mother answered the door at the family’s Westchester home Friday afternoon. She acknowledged that investigators had searched the house earlier in the day but said she did not know what they were looking for.

Neither Estes nor Sopo worked in the Republican primaries for Florida House districts 103 and 112, where voters were also targeted with the phantom absentee-ballot requests. It is unclear what, if any, involvement they could have had in those races.

District 103 stretches from Doral to Miramar; District 112 from Little Havana to Key Biscayne.

The Miami Herald found that 466 of 472 phantom requests in Congressional District 26 targeted Democrats. In House District 103, 864 of 871 requests targeted Republicans, as did 1,184 of 1,191 requests in House District 112.

During the primary, the campaign of Romero Roses, one of Garcia’s rivals, raised concerns about odd absentee-ballot requests in the race.

The phantom requests were first revealed in December by the grand jury examining absentee voting. Prosecutors said they could not track the hacker behind the requests because they were masked by 12 foreign IP addresses. But The Herald reported that they had not obtained information showing three additional domestic IP addresses as part of their initial inquiry, due to a miscommunication with the elections department.

A day after the Herald brought the domestic IP addresses to their attention in February, prosecutors said they would examine the ballot requests. At least two of the IP addresses were in Miami and could likely be tracked to the mystery hackers’ physical addresses.

Miami Herald staff writers Marc Caputo and Charles Rabin contributed to this report.