Washington (CNN) American attitudes about the US invasion of Iraq are nearly evenly split 15 years after the war began, a new Pew poll finds.

Forty-eight percent of respondents said the US made the wrong decision in using military force in Iraq, while 43% said it was the right decision.

The poll, which was conducted from March 7-14, found that more than half of Americans (53%) believe the US mostly failed to accomplish its goals in Iraq. Only 39% said they thought it had mostly succeeded.

Beliefs about the Iraq War continue to be largely divided along partisan lines. Sixty-one percent of Republicans and Republican-leaning independents say the US was right to use military force in Iraq, compared to only 27% of Democrats and Democratic-leaning independents. Half of conservative Republicans and 43% of moderate/liberal Republicans said they thought the US mostly succeeded in its goals, according to Pew. In contrast, only 18% of liberal Democrats and 39% of conservative/moderate Democrats said the same.

Overall, positive opinions of the war have declined since it began. Nearly three-quarters (74%) of respondents in May 2003 said they thought the US invasion was the right decision. That number dropped to its lowest point in Pew records -- 36% -- in late December 2007 and has not been above 50% since February 2006.

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