Update at 9:33 p.m. Romney Wins All Five Primaries; Delivers Remarks In N.H.:
With the GOP nomination all but secured, former Massachusetts Gov. Mitt Romney spoke to supporters in Manchester, N.H., Tuesday night after declaring victory in the five primary contests being held.
The Associated Press called the races for Connecticut, Rhode Island, Delaware and Pennsylvania for Romney quickly after polls closed. New York was also called for Romney shortly after he delivered his speech.
"After 43 primaries and caucuses, many long days and not a few long nights, I can say with confidence — and gratitude — that you have given me a great honor and solemn responsibility," Romney told the assembled crowd. "Tonight is the start of a new campaign to unite every American who knows in their heart that we can do better."
Despite the losses in Tuesday's contests, the AP is reporting that Newt Gingrich says he plans to finish a week of campaigning in North Carolina, but acknowledged that he needs to look realistically at where he stands.
Gingrich trails Mitt Romney in convention delegates and fundraising, yet he has vowed for weeks to campaign until the party's late-summer convention in Florida
Update at 9:01 p.m. - Romney Wins Penn.:
The Associated Press has called the GOP primary race in Pennsylvania, giving him wins in 4 out of the 5 primary contests Tuesday. Results in New York are still pending.
Update at 8:25 p.m. - R.I., Conn., Del.:
The Associated Press has called the GOP presidential primary contests in Rhode Island, Connecticut and Delaware for former Massachusetts Gov. Mitt Romney.
Our original post continues below:
Yes, this primary campaign is all but over. Still, voters in New York, Connecticut, Delaware, Pennsylvania and Rhode Island are still casting ballots.
And if you have any doubt about how settled this race is, Mitt Romney, the presumtive Republican nominee for president, is scheduled to deliver remarks from New Hampshire, a swing state that is not voting today.
One of the things to watch tonight is how Newt Gingrich, who along with Ron Paul are the only challengers Romney has left, performs in Delaware. In an interview with NBC News, Gingrich hinted if he didn't perform well in the state he would "reassess" his campaign.
But even if Romney loses Delaware, he will still be on track to securing the 1,144 delegates he needs for the nomination.
All of the polls close at 8 p.m., except for New York, which closes its polls at 9 p.m. ET. For the record, there are 209 convention delegates at stake tonight.