It was the Cubs' second consecutive victory after snapping their 12-game losing streak Monday, giving them their first series win since taking two of three from Atlanta from May 7-9.
"It's great, because the last two weeks, 12 games, we felt tired and frustrated," Soriano said. "Now the first two days we're feeling great, because we won two very good games."
Samardzija (5-3, 3.09 ERA) threw seven-plus strong innings, but exited in the eighth after Padres center fielder Will Venable's one-out RBI triple cut the Cubs' lead to one.
Camp entered and got Chris Denorfia to ground back to the mound, Yonder Alonso to line out to a diving Jeff Baker at first base and Carlos Quentin to fly out to left to get out of the jam.
"In a situation like that you just try to limit the damage," Camp said. "After I was able to get that ground ball back to me, that's a situation where you can kind of go for the jugular there."
"Yonder hit a bullet, and it was a great diving play," Padres manager Bud Black said. "There's nothing you can do about that."
Camp's work helped preserve the win for Samardzija, who struck out eight as he turned in his fourth outing of at least seven innings this month.
"Campy was outstanding," Samardzija said. "He did a great job."
Samardzija gave up a solo home run to Quentin in the fifth inning for the game's first run, but helped the Cubs regain the lead the next half-inning. Reed Johnson led off with a single and scored on a double by second baseman Darwin Barney, who advanced to third on a flyout by Koyie Hill.
Samardzija drove in Barney with a broken-bat single into left field off Padres left-hander Eric Stults (1-1, 2.92) to put the Cubs ahead.
"As a pitcher, it's kind of great because you're not expected to do anything," said Samardzija, who has recorded a hit in each of his last three starts. "You're expected to get out, so anything you do beyond that is just icing."
San Diego threatened in the sixth when Stults led off with a double to left-center. After Venable struck out, Denorfia lifted a fly ball into left-center field and Stults took off, but Soriano made a diving catch and threw to second for an inning-ending double play.
The Cubs left fielder's encore was a solo homer off Stults in the bottom of the inning. The home run was the third in the last four games for Soriano, who now has seven in his last 13 contests after going homerless in the season's first 30 games.
"That catch he made was tremendous," Cubs manager Dale Sveum said. "That was a huge, huge play in the game and then it never fails, you come up the next inning and he hits a home run after that."
Soriano's homer proved key as the Padres wouldn't go away. John Baker hit an RBI single in the seventh to give the Padres runners at first and second with one out.
Everth Cabrera followed with a hard chopper to Samardzija. He spun around and fired to second, but the throw was high and forced shortstop Starlin Castro to leap to snare it. Castro missed the bag coming down, but got Cabrera at first on a bang-bang play. Samardzija escaped unscathed, however, striking out pinch-hitter Jesus Guzman to end the threat.
The Cubs added an insurance run in the seventh when Barney doubled, advanced to third on a balk and scored on a passed ball, and in the eighth when Baker singled home Joe Mather.
Camp got the first out in the ninth, and James Russell recorded the last two to earn his first career save.
Chicago is in position to follow its 12-game skid with a pair of firsts Wednesday. A victory would give the Cubs their first series sweep and three-game winning streak of the season.
"We're just trying to get rolling here," Camp said. "We're playing good team baseball the last couple games, and hopefully we can carry it into tomorrow and on the road trip."