The age of exploration is over, at least when it comes to the Republican nomination for lieutenant governor: David M. Walker, former U.S. comptroller general, said Thursday he is closing his exploratory committee and running for a spot on the GOP under ticket.

State Rep. Penny Bacchiochi, R-Stafford, recently switched from an exploratory to a candidate committee. Heather Somers of Groton is running for lieutenant governor in tandem with Danbury Mayor Mark Boughton, a candidate for governor. Walker began his explorations in January.

“I assessed how my message was being received favorably and whether I could qualify for public financing,” Walker said. “Today, after 10 weeks of exploration, I believe the answer to these questions is a clear and resounding ‘yes.’ Therefore, I am announcing that I have decided to officially convert my exploratory committee for state office to a candidate committee for lieutenant governor.”

Walker, 62, of Bridgeport is a co-founder of the No Labels independent movement.

The time for exploring is growing short: Delegates to a Republican nominating convention will vote May 17 for the GOP ticket, starting by choosing whom to endorse among a half-dozen candidates for governor.

The previous night, Democrats will hold a more perfunctory nominating convention: All six state constitutional officers are seeking re-election.