The victory, in which lefty Franklin Morales (1-1) held the Padres to one run in six solid innings, gave the Rockies a 3-4 record on their first National League West road trip.
"All things considered, we played pretty well," Rockies manager Walt Weiss said. "It was a really tough series in San Francisco. Coming down here, having to play four games here, I thought we did a nice job.
"It would have been nice to win a series here, but those guys have a lot of good arms over there. It's tough to score runs in this park against that staff. Today was a big one, the last game of a road trip. Sometimes when it's not going your way early, you just hope the guys keep battling through that."
After the double by Dickerson, who started as the Rockies rested the scuffling Carlos Gonzalez, the Rockies found their clutch-hitting form.
In the two losses to the Padres (7-9), both close games, the Rockies (8-9) went a combined 3-for-20 with runners in scoring position. This time, after Dickerson's double and Troy Tulowitzki's walk, Justin Morneau doubled to right for one run, Wilin Rosario notched his fourth RBI of the series with a fielder's choice grounder for the go-ahead run, and Nolan Arenado added an RBI single.
"You can't underestimate what Morales did, kept us in the game," Morneau said. "We battled, and it started with 'Dickie' hitting that blooper over third, then we got a couple of big hits and we were good."
Morneau went 6-for-21 (.286) on the road trip, but four of the hits were for extra bases -- two home runs and two doubles. The Rockies need big contributions from Morneau, who signed a two-year, $12.5 million contract to fill the spot vacated by the retirement of longtime star first baseman Todd Helton.
"Justin is swinging the bat really well, taking a lot of good passes at the ball," Weiss said. "That's going to be big for us. We felt confident that there's a lot left with this guy. He's showing that's the case."
Before the seventh, Morales was the thread that kept the Rockies in the game.
Morales won a starting job out of Spring Training, but he was more hearty than efficient in his first two starts. He was briefly moved to the bullpen because of some good work by righty Jordan Lyles as a fill-in starter for the injured Tyler Chatwood. But lefty Brett Anderson's broken finger opened a new chance, which Morales grabbed.
"I don't think about that," Morales said. "I'm thinking only to do my job and help the team to win."
Xavier Nady's leadoff homer in the fourth on a hanging cutter was the only run off Morales, who held the Padres to four hits with five strikeouts and one walk in six innings. He entered the game with six walks in his previous two starts.
Because of his ability to command the strike zone, Morales dealt with just one runner in scoring position. Everth Cabrera doubled with two outs in the third and moved to third on Chris Denorfia's infield single. But Morales worked Jedd Gyorko into a harmless grounder to Arenado at third to end the inning.
"That's honestly the best I've ever seen him pitch," Padres center fielder Will Venable said.
Morales said he liked the game called by catcher Rosario. Their strategy flummoxed the Padres.
"He was effectively wild," Padres right fielder Chris Denorfia said. "He was hard to game plan against."
Kennedy finished with seven strikeouts in seven innings. The first Rockies baserunner came on a Tulowitzki walk to open the fifth, but two batters later, Kennedy ended the inning by coaxing a Rosario double-play grounder. Arenado doubled off the third-base bag to lead off the sixth with the Rockies' first hit. Colorado would grab control an inning later.
"He didn't miss a spot, didn't miss anything, for the first five innings," said Michael Cuddyer, who left with a left hamstring cramp after grounding out to begin the seventh. "For us to keep scratching and clawing and to take advantage of the very few mistakes he made was nice."
Rockies lefty reliever Rex Brothers, who had taken losses in his last two appearances, struck out two in a perfect seventh. Boone Logan gave up a Chase Headley pinch-hit single in the eighth but forced Cabrera into a double-play grounder. LaTroy Hawkins earned his fourth save.