It got the Seagulls back to winning ways as Chris Hughton celebrated his 100th league game in charge.
Baldock gave the visitors the lead in the 53rd minute with a neat half volley and the added a second with 22 minutes play from another Anthony Knockaert assist.
Hughton made two changes to the side that drew 1-1 with Ipswich Town, as Glenn Murray and Jamie Murphy replaced Tomer Hemed and Solly March in the starting line-up.
It was a much-needed victory for Albion after just three wins in seven games as they climb above previous leaders Newcastle, who play Aston Villa on Monday.
They are two points clear of their title rivals and seven ahead of Huddersfield in third, who held Manchester City to a 0-0 draw in the FA Cup today.