Cummings was selected by the Colorado Rapids in the 2007 MLS SuperDraft as a Round 3, number 31 overall pick. On 4 September 2010, Cummings scored two goals to help the Rapids to a 3–0 victory over Chivas USA at Dick's Sporting Goods Park. The performance led to him being voted as Major League Soccer Player of the Week for Week 23 of the MLS season by the North American Soccer Reporters (NASR). On 27 December 2010, it was announced that the Colorado Rapids had granted Cummings permission to trial with English Premier League club Aston Villa. On 17 January 2011, Aston Villa manager Gérard Houllier announced that Cummings had impressed on the trial. Due to work permit issues, a deal did not proceed.
Having returned to play for Colorado again in 2010, Cummings made his 100th MLS appearance for the Rapids on April 30, 2010, in a game against Chicago Fire.