Three years may be long enough for anything to happen. But consider this: it is hard to see the Conservative vote in 2015 being an increase on their 2010 showing. Since 2010 we've had the Euro crisis, George Osborne's U-turn fest, a healthy reminder of the symbiotic relationship between the Murdoch empire and the Tory party and the longest recession in more than 50 years. Even the IMF is losing patience. Hard to see the Tories storming to victory. Also, governments in power hardly ever increase their share of the vote. As Andrew Rawnsley has noted: "[f]or Mr Cameron to better his last general election result in the contest of 2015, he must do something that no Conservative prime minister has achieved for nearly six decades."
No matter, we can make a coalition with Labour. Er, not really. Even after the proposed boundary changes, Labour still has an in-built electoral advantage. This is a function of the way Labour's vote is spread around the country and the lower turnout in their safe constituencies. The UK Polling Report website explains this issue in detail.
So, if boundary reform is out the window (as a trade for the House of Lords debacle), Labour has won in 2015. If Labour fights an election on the existing boundaries and gets 37% of the vote (the Tories' 'winning' score in 2010), it can expect a 60-seat majority (it will get much more if, as expected, the Liberal Democrat vote collapses). If Labour maintains its current poll lead it gets a hundred-seat majority (all of these projections from the UK Polling report swingometer).
Getting a hung parliament in 2010 required a perfect storm: a very unpopular Labour party, a relatively untrusted Tory party and a healthy, if mostly wasted, Liberal Democrat vote in the middle. With Labour able to secure a comfortable parliamentary majority on less than 40% of the vote, we can expect neither offers of coalition nor electoral reform. The classic conservative mistake is to fear change more than the threat that forces that change. Killing off Lords reform just killed off the Tories' re-election chances.