Villa always carried the greater threat and will now be firm favourites to progress to a Carling Cup final date against either Manchester City or Manchester United, after Wednesday's second leg at Villa Park.
Blackburn's winless sequence now stretches to 12 games, although they did knock Chelsea out of this competition on penalties.
But it is hard to see how they will turn this semi-final around on the evidence of current form.
Aston Villa took a giant stride towards Wembley as James Milner's first-half goal gave them victory in the Carling Cup semi-final first leg at Blackburn Rovers.
Milner rounded off a devastating break after 23 minutes when he turned in Stewart Downing's cross as Villa swept the length of the field.
It gave Martin O'Neill's side a deserved advantage and provided a rich reward for Villa's attacking strategy as they dominated a jaded Blackburn side playing their second game this week.
Blackburn boss Sam Allardyce felt the full force of Ewood Park's fury as his side laboured to make any impression on Villa in the early exchanges, with the half-time whistle being greeted by a chorus of jeering.
But Blackburn improved hugely after the break only to find their luck was out as striker Nikola Kalinic twice hit the woodwork, firstly with a close-range header, then with a shot from 12 yards.
That would leave Allardyce and Blackburn with a fight for Premier League survival as their only goal for the rest of the season, a task to be played out in front of what appears to be an increasingly disenchanted Ewood Park public.
Allardyce employed Kalinic as a lone striker from the start - but he was knocking at a firmly closed door for long periods as he attempted to get the better of Villa's central defensive duo, Richard Dunne and James Collins.
Blackburn's best moment of a frustrating opening half came after just three minutes, when David Dunn's shot on the turn was only inches off target with Villa keeper Brad Guzan - in for the rested Brad Friedel - beaten.
Villa boss O'Neill had demonstrated his attacking intent by supporting Emile Heskey with the pace and width provided by Milner, Downing, Ashley Young and Gabriel Agbonlahor.
And the ploy paid off to perfection after 23 minutes when Milner concluded a sweeping Villa move that caught Blackburn on the break, turning Downing's cross beyond the reach of Paul Robinson at the near post.
Agbonlahor then thought he should have had a penalty when he was tripped by Christopher Samba.
It looked like he had a case but referee Mark Clattenburg not only ignored his appeals, but added insult to injury by booking the Villa striker.
Ewood Park was becoming an increasingly discontented place, with Allardyce the target for chants of "Big Sam Sort It Out" when Morten Gamst Pedersen placed a cross hopelessly into the travelling band of Villa supporters.
Robinson kept Blackburn in contention on the stroke of half-time, when he saved superbly down at his near post from Stiliyan Petrov's shot.
The reaction of Blackburn's fans as the whistle sounded for the interval told the tale of their satisfaction - and underlined the supremacy enjoyed by Villa.
Villa should have added a second in the opening moments of the second half when Young's cross flew right across the face of Blackburn's goal, with Agbonlahor just unable to add the finishing touch.
Blackburn finally broke the shackles when Kalinic rose to beat Dunne to Pedersen's cross, but could only direct his header against an upright from eight yards.
It was a passage of play that at least gave Blackburn's suffering supporters hope and Dunn provided further encouragement when he pulled a presentable chance wide from Pascal Chimbonda's knockdown.
Kalinic's luck was out again after 65 minutes, when the woodwork came to Villa's rescue once more as the striker met Chimbonda's cross with a crisp first-time shot.
Suddenly it was Villa's turn to be forced on to the back foot as Blackburn's effort to draw level gathered momentum.
Blackburn, however, always remained vulnerable to the Villa counter-attack, and Young reminded them of the threat when he burst into the penalty area but shot wide.
Both sides had chances in stoppage time, with Robinson saving well from Agbonlahor and Steven Nzonzi heading over - and the celebrations of the Villa fans at the final whistle suggested that they feel they have completed the most difficult part of their mission to return to Wembley.
The UK B-Losers Channel on BSkyB a few years ago, featuring "The Lost World"
