It may not be quite as crowded a field as that other Conservative leadership race, but Conservative senators will still have to choose between three of their current caucus colleagues when they go behind closed doors to select a successor to outgoing Senate leader Claude Carignan.

First out of the gate and still the presumptive front-runner — at least on paper — is Toronto-area Sen. Linda Frum, who was appointed on the advice of then-Prime Minister Stephen Harper in 2009 and has spent the last year and a half serving as caucus chair after being elected to the post shortly after the last election.

She’s also an unapologetic partisan who has been steadfast in expressing her scepticism over the ostensibly independent Senate appointment process instituted under Prime Minister Justin Trudeau.

In contrast, one of the two senators challenging her for the job is not only pledging to end the practice of whipped votes and allow senators to vote freely on all matters, he wouldn’t even require them to attend national caucus alongside the House Conservative caucus.

In a letter laying out his leadership plans, Nova Scotia Sen. Stephen Greene – who also was named to the Senate under Harper – would “restyle” the whip as a “caucus coordinator” and make it an elected position.

If elected, Greene promises to work with “other groups in the Senate,” including the Senate Liberals, the Independent Senators Group and those independent senators not currently aligned with any group, to ensure a “principled and organized Senate opposition.”

Rounding out the ballot is former CFL commissioner Sen. Larry Smith – also a Harper-era appointee — who has yet to publicly share any details from his campaign platform.

Both Smith and Greene are on the record as supporting Maxime Bernier in the party leadership race, while Frum has yet to come out publicly in favour of any candidate.

Also on the agenda tomorrow: Conservative senators will have to pick a new caucus chair from the two Newfoundlanders vying for the job, Sen. David Wells and Sen. Fabian Manning.

Meanwhile, incumbent deputy leader Yonah Martin is set to continue in her role as no Conservative senator has stepped forward to run against her. Both the whip and deputy whip are chosen by the leader, which means those positions won’t be filled until Carignan’s replacement is installed.

The meeting is scheduled to get underway at noon on Tuesday, with results expected to be made public just before the Senate reconvenes at 2 p.m.