Two innings later, Bailey finished it off smoothly. He jumped to glove Brandon Crawford's high comebacker, struck out Tony Abreu and retired Blanco on a grounder to third baseman Todd Frazier.
"Going into the eighth and ninth I just said, 'Why the hell not?' Here we go again," Bailey said.
Justin Verlander, Mark Buehrle and Roy Halladay are the only other active pitchers with a pair of no-hitters. Halladay, of course, threw one of his in the postseason against the Reds in 2010.
When Votto caught the throw for the final out, Bailey raised both arms in triumph, reminiscent of that grand moment in Pittsburgh last September, then hugged catcher Ryan Hanigan. This time, Baker got to celebrate too - he was in a hospital in Chicago being treated for a mini-stroke last September.
Teammates poured onto the field to celebrate and doused Bailey with a red sports drink.
It was the 16th no-hitter in Cincinnati history. No Reds pitcher had thrown a no-no at home since Tom Browning's 1-0 perfect game against the Dodgers at Riverfront Stadium on Sept. 16, 1988.
Bailey became the third pitcher in the history of baseball's first professional franchise to get more than one.
Vander Meer threw the only back-to-back no-hitters in major league history in 1938, beating the Boston Braves and Brooklyn Dodgers. Maloney had a no-hitter at Wrigley Field in 1965 and one at home against Houston in 1969.
The Giants were no-hit for the 16th time. The last three pitchers to hold them hitless were all named Kevin - LA's Gross in 1992, Florida's Brown in 1997 and Philadelphia's Millwood in 2003.
Bailey was facing a lineup in a deep funk - two runs or less in nine of San Francisco's last 12 games.
Last year was the season of the no-hitter, with seven in all, which tied the modern record. By this point, five had been thrown. So far in 2013, there had been only two close calls.
Texas' Yu Darvish was working on a perfect game when he gave up a two-out single in the ninth to Houston's Marwin Gonzalez during a 7-0 win on April 2. Detroit's Anibal Sanchez gave up a one-out single in the ninth to Minnesota's Joe Mauer in a 6-0 win on May 24.
Bailey became the first to take one all the way this year.
Votto had a sacrifice fly off Tim Lincecum (4-9), and Brandon Phillips hit a two-run homer for all the help Bailey would need.
Lincecum had some of his best moments last season in Cincinnati. Relegated to the bullpen after losing 15 games during the regular season, he went 4 1-3 innings in relief to help the Giants win Game 4 and, eventually, their division series, the first step toward a World Series title.
But there was no stopping Bailey this time.
Shin-Soo Choo hit Lincecum's fifth pitch deep to right. Hunter Pence jumped above the wall and had the ball deflect off the heel of his glove back into play. The umpires initially ruled it a home run, but overturned the call after a review and gave Choo a double. He eventually scored on Votto's sac fly.
Phillips hit a drive into the first row in left field in the sixth inning, his 12th homer for a 3-0 lead.