Hillary Clinton and Bernie Sanders are now virtually tied nationally, according to a Quinnipiac University poll released Friday.

The poll, which was conducted in the two days after Monday's Iowa caucuses, found that 44 percent of Democratic voters support Clinton and 42 percent said they back Vermont's independent senator. Eleven percent said they are undecided.

In the last poll conducted in late December, Clinton was leading against Sanders 61 percent to 30 percent.

Clinton was declared the official winner of the caucuses on Monday night, winning by 0.3 percentage points. As for the New Hampshire primary on Tuesday, Sanders leads Clinton by 20 percentage points, according to an NBC News/Marist poll released Thursday.

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The Quinnipiac poll found that Sanders is the strongest candidate in the Democratic race in general election match-ups. If Sanders and Donald Trump won their respective nomination, for example, Sanders would defeat Trump by 10 percentage points. If it were Clinton against Trump, she would beat him by 5 percentage points. Sanders would also beat Sen. Ted Cruz by 4 percentage points, but he would be tied with Sen. Marco Rubio.

If former New York City Mayor Michael Bloomberg launched an independent run, however, the poll found that he would hurt Sanders more than he would hurt any of the GOP presidential candidates.

Among Republicans, the survey found that Rubio is the strongest candidate in his field to win the November general election. But for the primary, Trump still leads the GOP pack with 31 percent support nationally, followed by Cruz with 22 percent and Rubio with 19 percent. Nine percent said they're still undecided.

The poll surveyed 1,125 registered voters between Feb. 2 and 4. There's a 4.4 percentage point margin of error for the 507 Republicans surveyed and a 4.5 percentage point margin of error for the 484 Democrats who were polled.