City Democrats are headed back to the polls today to decide two runoff primary elections.

Bill de Blasio and Mark Green are battling for public advocate.

In the primary, de Blasio picked up a little less than 33 percent to Green's 31 percent.

De Blasio has the backing of current Public Advocate Betsy Gotbaum and the New York Times. Green announced he has the support of Robert Kennedy Jr. and the Daily News.

Meanwhile, John Liu and David Yassky are squaring off in the race for city comptroller.

Liu, who received 38 percent to Yassky's 30 percent in the primary, is backed by former Mayor David Dinkins, and former comptroller candidate and City Councilman David Weprin.

Yassky has the support of former rival Melinda Katz, also of the City Council.

Normally, the day before the election is a busy day for the candidates. But given that Monday was Yom Kippur, the holiest day on the Jewish calendar, Green and Yassky did not campaign at all.

Their respective opponents, however, were out searching for votes. Bill de Blasio and John Liu appeared together Monday morning at a rally held by Workers United.

De Blasio said there was a deliberate effort to keep things low-key and respectful.

"We talked to a lot of our Jewish supporters, and I have supporters all over the Jewish community in the five boroughs, and the answer we heard was, 'it's perfectly appropriate to campaign today outside of Jewish neighborhoods,'" said De Blasio. "And I think it's also important to keep a positive tone."

Yassky has released television advertisements and campaign fliers in recent days accusing Liu of being untruthful on a number of issues, questioning whether he really worked in a sweatshop as a child. But on Monday, Liu shot back.

"With just a few days to go, a highly-negative campaign has been aired on TV, on radio. Mailboxes have been polluted with that garbage," Liu said. "The fact of the matter is, this is a smear campaign. They're questioning my integrity. I'm very proud of my integrity, my record. And voters are not going to go for this kind of smear campaign."

While there was historically-low voter turnout in the primary earlier this month, many are expecting turnout to be even lower for Tuesday's runoff. As a result, candidates are focusing on simply getting out the vote.

Tuesday's winners will move on to compete in November's general election.