The Fine Gael leader, Mr John Bruton, will next week promote up to five younger members and drop at least one senior frontbench member in an effort to inject new life into his party.
The party whip, Mr Sean Barrett, who is retiring at the next general election, is expected to leave the front bench in the reshuffle, while those promoted are expected to include Mr Billy Timmins, Ms Deirdre Clune and Mr Charles Flanagan.
Buoyed by the party's strong by-election performance, Mr Bruton will announce the changes on Wednesday or Thursday next.
Any prospect of a challenge to Mr Bruton's leadership in the near future has evaporated, and the changes will further consolidate Mr Bruton's position.
The two most senior figures under Mr Bruton, deputy leader Mrs Nora Owen and finance spokesman Mr Michael Noonan, are expected to remain in their present positions.
While some close to Mr Bruton argue that Mr Noonan should be made deputy leader, Mrs Owen, who is very active in the position, is unlikely to relinquish it.
While there is speculation that the position of a number of other front-bench members, such as health spokesman Mr Alan Shatter and marine spokesman Mr Michael Finucane, might be under threat, senior party sources say Mr Bruton will be reluctant to demote senior figures.
However, a number of spokespersons - including Mr Jim Higgins (justice), Mr Alan Dukes (environment) and Ms Frances Fitzgerald (defence) - are expected to move from their positions but remain on the front bench.
There is speculation that Mr Dukes, a former minister for justice, could replace Mr Higgins as justice spokesman.
Mr Billy Timmins, first elected in 1997, is junior defence spokesman and is likely to be given the senior defence position as Ms Fitzgerald moves to another portfolio.
The deputies being promoted may be put on to an expanded front bench, or may be given specific, tightly focused roles which are not full front-bench positions, according to senior sources.
The promotion of Mr Charlie Flanagan, director of elections for the the party's impressive Tipperary South campaign, will represent a revival of fortunes for the Laois-Offaly deputy.
Mr Flanagan backed the last heave against Mr Bruton and, while regarded as an able deputy, received no government position during Mr Bruton's 1994-97 term as Taoiseach.
The likely promotion of Ms Deirdre Clune - currently junior environment spokeswoman, who replaced her father, Mr Peter Barry, as a Cork South Central Fine Gael deputy in 1997 - would also represent rapid advancement.
Mr Brian Hayes and Mr Denis Naughten, both junior spokesmen, may also be considered before Mr Bruton announces his new team.