A Liberal Democrat party member has suggested that leader Sir Menzies Campbell was "over-promoted".
Sir Menzies Campbell was once foreign affairs spokesman
Linda Jack, a member of the party's policy committee, said he "hasn't captured the imagination of the party or the country".
She did say he was "brilliant" before as foreign affairs spokesman.
Deputy leader Vincent Cable rejected the criticism and said the party was not in a "dissimilar" position to the position it had been in recent years.
'Up and down'
Ms Jack, who stood as a candidate at the last election, said of Sir Menzies on BBC Radio 4's World at One: "Unfortunately it's the case where he has perhaps been over-promoted.
"Someone can be a brilliant man and have incredible intellectual powers and all the rest of it but if that doesn't translate in to leadership skills then whoever your leader is you've got a problem with them."
The Liberal Democrats have not managed to make opinion poll gains in recent surveys - while Labour has gained strength under new PM Gordon Brown.
But Mr Cable said: "The polls are up and down and we're not in a greatly dissimilar position to we were in earlier parliaments.
"What's happening in a broader context is that Gordon Brown has just taken over, he's having a honeymoon, he's getting a lot of attention, quite rightly so, and if you're an opposition party like ourselves, you're not getting the focus of attention that the Government is."