AUGUSTA — Democratic U.S. Rep. Joseph E. Brennan took to the airwaves for the first time in the gubernatorial campaign Monday, rolling out two radio advertisements touting himself as a candidate of both fiscal conservatism and compassion.

In an answering salvo to Republican Gov. John R. McKernan’s earlier radio and television ads, Brennan underscored his criticisms of the incumbent’s managerial performance, calling for “a government that can handle the basics.”

“Let’s get Maine back on track with strong, experienced leadership,” both ads declared.

McKernan, meanwhile, announced the expected assignment of top aide Sharon Y. Miller of Cape Elizabeth to the position of campaign manager.

Miller, taking a leave from her post as the governor’s chief of staff, assumes formal command of an organization already stocked with veterans from past McKernan campaigns, including Operations Manager Sandra E. Tuttle, Finance Chairman Howard H. Dana Jr. and Administrative Assistant W. Davis Lackey Jr.

Brennan’s paid broadcast debut and the McKernan organizational structuring put both campaigns at their highest degree of battle readiness yet, only a little less than four months from the November general election.