Four of the six candidates have been eliminated, with only Conservative Antony Stansfled and Labour's Tim Starkey remaining.
The Tory is taking a lead of around 20,000 votes over his Labour counterpart into the second round.
The votes of everyone who put Mr Stansfeld and Mr Starkey as their second preference will now be added to their totals.
Mr Stansfeld picked up the most votes in 13 of the 16 districts, with Mr Starkey topping the polls in Slough, Reading and Oxford.
Mr Stansfeld won 76,011 votes to Mr Starkey's 56,631.
The turnout across the region was just 13.3%.