When Rep. David Rivera announces Friday that he's switching races from state Senate to Congress, he'll no longer be able to claim this title: front-runner.

That title more likely goes to Senate Republican leader Alex Diaz de la Portilla (assuming he enters the race). He appears to be among the best-known and best-liked of the potential candidates to run for U.S. Rep. Mario Diaz-Balart's seat, according to a survey of 300 Republican voters conducted by Hill Research Consultants, which conducts polls for retiring U.S. Rep. Lincoln Diaz-Balart. Hill also polled for Sen. Mel Martinez in his successful 2004 race.

The poll isn't a straight matchup, but instead tests the name ID of the candidates and their favorable/unfavorables. The Miami-Dade commissioner is better known than DLP by a percentage point (well within the poll's error margin), but his negatives are almost twice as high. Rivera comes in third by any measure.

It's little surprise DLP, who could announce as early as next week, does so well. Not only has he been in office for a long time, his brother Miguel Diaz de la Portilla was a county commissioner and ran for county mayor. His other brother, Renier Diaz de la Portilla, is a School Board member. So the family name blankets the county. Still, the district does extend to Naples.

The big surprise: Carlos Curbelo. U.S. Sen George LeMiuex's Florida director, Curbelo has strong name ID and likely earned it as a spokesman for both Diaz-Balarts in the 2008 campaign season. He has never been on the ballot, save a Miami-Dade Republican Executive Committee chairman race where he lost by just one vote to Rivera. In a season when political outsiders might have an edge, the numbers are encouraging for Curbelo, who's meeting with the National Republican Congressional Committee Friday.

Here's the list:

Name Name ID   Fav.   Unfav.  Unsure, but Familiar
Joe Martinez    68   34  17   17
Alex Diaz de la Portilla 67  39   9    18
David Rivera 41   24   5    12
Carlos Curbelo 32   11   5    16
Carlos Gimenez   29   11   5    14
Mike Pizzi   22   10   3 9