Polls show the main parties are neck and neck to take control of Commons.
And locally parties need to find fewer than 1,526 votes to take one local seat, with others needing to poll many more thousands of votes to win.
Based on 2010 general election results, this is what parties need to do to win.
The narrowest contest this year is likely to be the Colne Valley constituency.
In 2010 Conservative Jason McCartney gained the seat from Labour, winning with 20,440 votes in the highest turnout of all Kirklees constituencies.
But 4,837 votes behind him were the Liberal Democrats (15,603), with Labour pushed into third place (14,589).
This year Labour are challenging for the seat with polls suggesting there could be as little as 1% in it.
The turnout in 2010 was 55,296 (69.4%) and the other candidates were: BNP (1,893); UKIP (1.163), Green (867) and TUSC (741).
Here's a look at how the national polls are tracking:
Labour will be hoping to win the seat back from the Conservatives, who gained it from Labour in 2010.
Then Simon Reevell polled 18,898 votes ahead of Labour on 17,372. Labour has seen Dewsbury as a key seat with high-profile visits throughout the election campaign.
The turnout in 2010 was 54,008 (68.7%) and the other candidates were: Lib Dem (9,150); Independent (3,813); BNP (3,265); Green (849); English Democrat (661).
Kirklees’ safest seat is held by Barry Sheerman. In 2010 Labour won with 15,725 votes in the lowest local turnout - 4,472 votes behind him were the Conservatives.
The turnout in 2010 was 40,724 (62%) and the other candidates were: Lib Dem (10,023); Green (1,641); BNP (1,563) and TUSC (319).
Batley & Spen:
Labour’s Mike Wood held the Batley & Spen seat 4,406 votes ahead of his nearest rival, the Conservatives.
Mr Wood has now stepped down with Labour selecting Jo Cox to contest the seat.
The turnout in 2010 was 51,109 (66.8%) and the other candidates were: Lib Dems (8,095); BNP (3,685) and Green (605).
If you want to keep abreast of what's happening locally here's a list of who to follow: