Almost two million general election votes in the West Midlands were "wasted by an outdated" voting system, according to the Electoral Reform Society.
Analysis of the May 7 poll also found 33 of 59 MPs in the region failed to win the support of over half their electorates.
They revealed the MP with the lowest proportion of the vote was David Winnick who was elected with just 39 per cent backing him.
And it pointed out 1.3 million people voted for parties which came away with nothing in the West Midlands.
UKIP, the Lib Dems and the Green Party took a quarter of the vote but received nothing in the region while the Conservatives wound up with 58 per cent of the seats on a 42 per cent share of the vote.
The society, which would like to see a form of proportional representation introduced, claims this highlights how unfair the current voting system is - especially as this is no longer a two- or even three-party system.
Chief executive Katie Ghose said: "That nearly two million people's votes in the West Midlands were effectively wasted on May 7 is a shocking indictment of a voting system in crisis.
"Our winner-takes-all voting system means millions of people's voices are being ignored, not just in the region but across the UK.
"As we've demonstrated, there are much fairer ways to elect MPs. We are the last country in Europe to use first past the post - and it's time our democracy caught up with the 21st century.
"People are shopping around nowadays and voting for a range of parties, as the TV debates showed, yet our two-party voting system is failing to reflect that.
"It's time we reformed our voting system to ensure that the 2020 election doesn't break another record for the most disproportionate result in UK history."
2015 election result in the West Midlands:
Conservatives - 41.5 per cent of vote and 34 seats
Labour - 33 per cent of vote and 25 seats
UKIP - 15 per cent and zero seats
Lib Dems - 5.6 per cent and zero seats
Greens - three per cent and zero seats
According to the Electoral Reform Society, West Midlands seats under alternative electoral systems:
- Under a single transferable vote the Conservatives would have 30 seats, Labour 22, UKIP six and Lib Dems one.
- Under a party list system, the Conservatives would have 23 seats, Labour 19, UKIP nine, Lib Dems three and Greens one
- Under alternative vote (as offered in the 2011 referendum) the Conservatives would have 37 and Labour 22.