The transportation tax approved by Hillsborough County voters promises to give HART, the county's mass transit agency, the money it needs to finally transform the area's transportation system. But there is a disconnect between the voters' ambitions and the pool of candidates to become the agency’s new chief executive. HART should slow down the hiring process and consider reopening the search.A HART panel will meet Monday to decide which of the four finalists for chief executive will move to the next phase. Of the four, one already works for HART, and two others come from agencies that would be smaller than Hillsborough's newly invigorated transit operation. How that meets the aspirations of this new era is anybody's guess. With billions in new funding in the coming years, HART needs an experienced leader and visionary who can reset the region's bar. HART's board owes it to voters and taxpayers to get this right.The agency should work with its search firm to expand the talent pool. County Commissioner Stacy White's unfortunate lawsuit against the tax may have scared away potential applicants. But this still is a vibrant, growing metropolitan area, with new money and a renewed focus on better connecting millions across the region. Voters in November said they have higher expectations. HART can begin to fulfill those only by aiming higher for a new leader.