Commons leader Jack Straw's Lords reform proposals have met with a mixed response from Labour MPs and peers.
Jack Straw backs a 50% elected House of Lords
Labour Party sources said speakers at a meeting to debate the plans had been "60/40" in favour of Mr Straw's ideas.
But some Labour MPs were also reported to be planning to revive a campaign for a mainly elected second chamber.
Mr Straw, who favours a 50/50 split between elected and appointed peers, will set out his proposals in a White Paper to be published on Wednesday.
It will set out seven options for reform and there will be a Commons vote on the exact proportion of peers to be elected, with the options ranging from none to all being elected.
Labour backbenchers and peers were reported to have expressed a "vast range of views" about the White Paper at a meeting of the Parliamentary Labour Party on Monday night.
It is understood there was particular discussion of Mr Straw's plans to have a preliminary vote on options for the proportion of elected Lords.
Under the current plan, MPs will vote first - in the Commons chamber - on whether they want any kind of upper house at all and then whether the current House of Lords should be reformed.
MPs will then, in an unusual move, vote on seven options for reform: all elected; 80% elected, 20% appointed; 60% elected, 40% appointed; half and half; 40% elected, 60% appointed; 20% elected, 80% appointed; and all appointed.
Instead of voting in the division lobbies, MPs will indicate their preferences in order on a ballot paper.
Under this alternative vote system, the least popular option will be knocked out and its second preferences redistributed until one option achieves a majority.
Some Labour MPs are planning to campaign for a mainly elected House of Lords, to encourage MPs to vote for any option which would mean that over 50% of the upper house would be elected.
At Monday's meeting, the veteran Labour backbencher Dennis Skinner also warned candidates for the Labour party deputy leadership against discussing the cash-for-honours investigation in public.
Mr Skinner was heard to tell the meeting that contenders should "keep your traps shut and remember Scotland and Wales", referring to May's local elections.
There are concerns in the Labour Party that the cash-for-honours investigation could affect Labour's fortunes in the local elections.