NEW YORK - New Yorkers will head to the polls tomorrow for Primary Day.

In the race for the Democratic bid for mayor, the latest Quinnipiac University poll shows public advocate Bill de Blasio ahead of his competition with 39 percent of likely voters. He needs 40 percent of the vote to guarantee a spot in the November general election.

Former Comptroller Bill Thompson is polling second, City Council Speaker Christine Quinn trails in third and Anthony Weiner is in fourth with an expected 6 percent of the vote.

The race for comptroller is also heating up. In the Democratic primary, Manhattan Borough President Scott Stringer has a growing lead over former Gov. Eliot Spitzer.

The Quinnipiac University poll shows Stringer with 50 percent of votes versus Spitzer's 43 percent. Still, 13 percent of respondents say there's a good chance they'll change their minds by tomorrow.

Scanners that have been used in general elections over recent years will not be used during Tuesday’s primary.

Michael J. Ryan, of the Board of Elections, says that there would not be enough time in between the primary and potential runoff to reprogram all of the electronic voting machines.

Election officials said that they are confident that the voting machines, used during the 1960s, will be fully functional while New Yorkers head to the polls.

Officials say the scanners will be used during the November general election.

The nonpartisan group Common Cause is stepping in to make sure the machines don't cause any problems tomorrow. The group is relaunching PollWatchUSA, a mobile app that will allow New Yorkers to report problems at the polls.

Polls will be open from 6 a.m. to 9 p.m.