Today is the day election spending rules kick in and the campaign for 2015 officially begins. Here are the key dates for your diary:

• December 19: Long campaign begins. Candidate spending limited to £30,700, plus 9p per voter in county (rural) constituencies, and 6p per voter in borough (urban) constituencies.

• January 5: House returns from Christmas recess.

• February 12-23: February recess.

• March 18: George Osborne delivers the final budget of the parliament. He only has a few working days to get it through before…

• March 30: Parliament dissolves. Short campaign begins. Spending restrictions tightened to £8,700, plus 9p per voter in county constituencies and 6p per voter in borough constituencies.

• May 7: Election day.

138 days to go…