WASHINGTON (AP) — Mitt Romney and Newt Gingrich are using transparency as a club against each other.Gingrich pressed Romney to release his tax returns until the former Massachusetts governor relented this week.Romney badgered the former House speaker to disclose more information about work he was paid to do after leaving Congress.But there's not an across-the-board commitment to openness in either campaign.For example, Romney and his staff are keeping records from his term as governor from becoming public.Openness advocates say they don't know what changes, if any, Romney and Gingrich might propose to the nation's pre-eminent open records law or other transparency initiatives advocated by the Obama administration. But they say the signals from the GOP campaign are worrisome.EDITOR'S NOTE _ An occasional look behind political rhetoric.