Complex sentence: The failure to select a President caused the 2007 general election to be brought forward, since the constitution states that a snap general election must be called to overcome the parliamentary deadlock, if a president is not elected.
Split into simpler sentences: The failure to select a President caused the 2007 general election to be brought forward. This is due to the Constitution's statement that a snap general election must be called to overcome the parliamentary deadlock if a president is not elected.