ANNAPOLIS, NOV. 20 -- After 10 years as one of the budget leaders in the Maryland General Assembly, Del. Nancy K. Kopp (D-Montgomery) had impeccable credentials in education policy and financing.

Today, Kopp traded that platform -- her subcommittee chairmanship -- for the post of speaker pro tem, nominally the second-ranking leader in the House of Delegates.

What that means for Kopp and Montgomery County's influence in the legislature is as yet unclear. But Kopp, 46, a workaholic by reputation, has one test of whether it was a good exchange.

"I wouldn't make the change unless I was sure the position I was taking is at least of equal power," said Kopp, a full-time legislator from Bethesda.

During a Democratic caucus today, Kopp was nominated for speaker pro tem. Her selection in January, after the General Assembly convenes, is assured by virtue of Democrats controlling 116 of 141 seats in the House. Kopp will succeed Del. Dennis C. Donaldson (D-Prince George's), who did not seek reelection to the legislature this year.

Kopp is viewed as more likely to reach out to women and junior members, who often have chafed under the leadership of Speaker R. Clayton Mitchell Jr. (D-Kent).

"I'll take an active role in helping bring some less senior members into leadership, finding different ways to involve them in decisions or policy issues of substance," said Kopp, who on Jan. 9 will begin her fifth term at the State House.

Fellow delegates from Montgomery hope Kopp's new position will elevate the views of the county, especially in debate over tax increases. "It's good for Nancy and good for Montgomery," said Del. Gene W. Counihan (D-Montgomery). "This really enhances Montgomery's position in the House leadership."

But Kopp is being cautious about claiming greater influence. "If I did have, I wouldn't say," Kopp said.

Kopp, who led the House ticket Nov. 6 in her Montgomery County district, has a history of close ties to Mitchell and Del. Charles J. Ryan (D-Prince George's), the appropriations committee chairman. "Nancy will play one of the most key roles that any speaker pro tem has ever played," Mitchell said.