Neil Kinnock wasnt the only standard bearer of the right of the party.
Uh, Neil Kinnock was a standard bearer of the left of the party when he took over. He'd made his name as a left-wing maverick in the seventies and had never been a minister, but he had no truck with Benn etc.
We've had threads on this before alt_historian - you may want to look them up. Long story short, it was impossible that the SDP were going to break the mould in '83 for a number of reasons:
Namely:
- High party identification in both the Tories and Labour. The Labour right, such as Hattersely, Smith, Healey etc were completely bound into Labour, no matter how left-wing it got; less scrupluous types just worried (rightly) that they would never win re-election in their constituencies if they defected. They were never going to defect and cripple the party, which is what the SDP relied upon in large part. The same can be said for Ian Gilmour etc with the Tories - the 'wet' element of the Tories was excluded after Thatcher's cabinet reshuffle of '81, they were pilloried, mocked, and yet they never went over to the SDP. Taking in the moderate elements from both parties was never more than a pipe-dream.
- The electoral system meant that they could never break through. Labour was, through it's inner city constituencues, basically locked into, at the minimum, 200 seats or so. The Alliance was never going to match this. Even if they trump Labour and come in second in the popular vote, which is very plausible, then they would have only got, max, about 100 seats.
- The SDP never established any distinctive identity beyond being a middle class protest party. They didn't have the draw on people that Labour and the Tories had, they never really could. All the joys of being a catch-all party - your vote is very weak.
There are plenty of ways that you could make the Alliance a lot more formidable than it was historically, which have already been outlined - more polarised Labour and Conservatives, Falklands goes bad, etc. But they weren't going to breakthrough in '83; their main realistic strategy was to bring the Tories down so low that coalition becomes a prospect. But that itself brings up all sorts of problems.