Notional results for a UK general election on 5 May 2005 Yorkshire and The Humber, England - by majority
| Constituency | Winning party | Valid votes | Majority (votes) | Majority (%) |
| Barnsley East | Lab | 32,136 | 18,298 | 56.9% |
| Sheffield, Brightside and Hillsborough | Lab | 33,230 | 18,801 | 56.6% |
| Normanton, Pontefract and Castleford | Lab | 42,287 | 20,608 | 48.7% |
| Wentworth and Dearne | Lab | 38,533 | 17,551 | 45.5% |
| Sheffield South East | Lab | 36,536 | 15,843 | 43.4% |
| Rotherham | Lab | 33,550 | 13,865 | 41.3% |
| Leeds West | Lab | 35,283 | 13,699 | 38.8% |
| Richmond (Yorks) | Con | 50,217 | 19,450 | 38.7% |
| Barnsley Central | Lab | 30,897 | 11,839 | 38.3% |
| Leeds East | Lab | 35,829 | 13,689 | 38.2% |
| Leeds Central | Lab | 34,008 | 12,916 | 38.0% |
| Hemsworth | Lab | 38,421 | 14,026 | 36.5% |
| Kingston upon Hull East | Lab | 32,753 | 11,740 | 35.8% |
| Kingston upon Hull West and Hessle | Lab | 27,688 | 9,430 | 34.1% |
| Sheffield, Heeley | Lab | 37,773 | 12,340 | 32.7% |
| Doncaster North | Lab | 37,765 | 12,027 | 31.8% |
| Don Valley | Lab | 38,345 | 11,333 | 29.6% |
| Thirsk and Malton | Con | 49,540 | 14,117 | 28.5% |
| Rother Valley | Lab | 40,597 | 11,558 | 28.5% |
| Doncaster Central | Lab | 37,774 | 10,325 | 27.3% |
| Kingston upon Hull North | Lab | 28,089 | 7,384 | 26.3% |
| York Central | Lab | 39,907 | 10,344 | 25.9% |
| Scunthorpe | Lab | 34,230 | 8,638 | 25.2% |
| Bradford South | Lab | 35,198 | 8,444 | 24.0% |
| Skipton and Ripon | Con | 49,484 | 11,596 | 23.4% |
| Great Grimsby | Lab | 32,964 | 7,654 | 23.2% |
| Huddersfield | Lab | 35,362 | 7,883 | 22.3% |
| Morley and Outwood | Lab | 41,389 | 8,669 | 20.9% |
| Penistone and Stocksbridge | Lab | 42,179 | 8,617 | 20.4% |
| Wakefield | Lab | 41,990 | 7,349 | 17.5% |
| Harrogate and Knaresborough | LD | 49,212 | 7,980 | 16.2% |
| Sheffield, Hallam | LD | 45,852 | 7,416 | 16.2% |
| Leeds North East | Lab | 43,604 | 6,762 | 15.5% |
| Sheffield Central | Lab | 33,225 | 5,025 | 15.1% |
| Bradford East | Lab | 36,705 | 5,227 | 14.2% |
| Batley and Spen | Lab | 44,744 | 6,060 | 13.5% |
| East Yorkshire | Con | 47,195 | 6,284 | 13.3% |
| Pudsey | Lab | 44,309 | 5,204 | 11.7% |
| Elmet and Rothwell | Lab | 53,187 | 6,078 | 11.4% |
| Haltemprice and Howden | Con | 48,271 | 5,080 | 10.5% |
| Keighley | Lab | 46,312 | 4,852 | 10.5% |
| Dewsbury | Lab | 45,036 | 3,999 | 8.9% |
| Halifax | Lab | 39,773 | 3,481 | 8.8% |
| Bradford West | Lab | 36,583 | 3,050 | 8.3% |
| Brigg and Goole | Lab | 41,010 | 3,217 | 7.8% |
| Beverley and Holderness | Con | 49,689 | 3,097 | 6.2% |
| Cleethorpes | Lab | 43,587 | 2,640 | 6.1% |
| Leeds North West | LD | 41,572 | 2,064 | 5.0% |
| Selby and Ainsty | Con | 47,833 | 2,060 | 4.3% |
| Calder Valley | Lab | 47,656 | 1,303 | 2.7% |
| Scarborough and Whitby | Con | 46,912 | 1,245 | 2.7% |
| Colne Valley | Lab | 50,430 | 1,267 | 2.5% |
| Shipley | Con | 46,551 | 450 | 1.0% |
| York Outer | LD | 46,030 | 203 | 0.4% |
Estimates of the 2005 general election result in new constituencies
Colin Rallings and Michael Thrasher, then at the University of Plymouth, produced estimates of the 2005 general election result as if the new constituencies recommended by the separate Parliamentary Boundary Commissions for England, Wales and Northern Ireland had then been in existence.
The Elections Centre, established by Professors Colin Rallings and Michael Thrasher, moved to the University of Exeter in 2003.