Now this version of the Red Sox is going to find out if momentum is a living, breathing thing. Mike Carp delivered the second straight walkoff with an RBI single in the 10th inning yesterday to finish off a 4-3 victory over the Chicago White Sox at Fenway Park. Any kind of win in any kind of way is all the Red Sox are asking for nowadays, especially with one of the worst homestands in recent memory coming to an end. The Sox desperately needed these last two victories to finish off the 10-game showcase in front of the home crowd at 3-7. Now, heavily limping but not completely crushed, they are heading to Houston tonight to start the first game of the final series before the All-Star break. “Momentum is a funny thing and this game is a funny thing,” Sox catcher David Ross said. “We are going to focus on tomorrow and it would be nice to go into Houston and play well and go into the All-Star break giving the front office a little something to think about.” The 2013 World Series champions were built on wins like the ones they’ve had the past two nights. Last year, there probably would have been a much more consistent offense to go along with those good vibes, but the timeliness of the hits yesterday outmatched the quantity. Carp, pinch-hitting for Ross in the 10th, came up with runners on first and second after Daniel Nava, also pinch-hitting in the frame for Jonny Gomes, worked a leadoff walk. Stephen Drew was intentionally walked by White Sox reliever Ronald Belisario to put runners on first and second with one out.