The pro-business group's endorsement could mean big money for Hasner. The Chamber has been spending heavily on ads boosting candidates it supports and attacking incumbent Democrats in congressional races across the country.

Hasner is running in a redrawn Florida district currently held by Rep. Allen West (R-Fla.), who is running for reelection in a different district. Hasner will face the winner of the Democratic primary, where Lois FrankelLois Jane FrankelDemocrats planning protests for Trump’s first State of the Union Dems to invite sexual assault survivors as guests to Trump's State of the Union: report Democratic women unite on demand to investigate Trump MORE has the early lead.