Lynne Sladky, Associated Press
First Lady Michelle Obama waves to volunteers during a sound check for the Democratic National Convention in Charlotte, N.C., on Monday, Sept. 3, 2012.

WASHINGTON — Democrats have passed a party platform at their national convention that echoes President Barack Obama's call for higher taxes on wealthier Americans, while backing same-sex marriage and abortion rights.

Delegates approved the platform on Tuesday. It reflects Obama's argument that his work isn't done and that he deserves another four years to complete the job.

The platform says the economy is growing again under Obama, that the manufacturing industry is stronger under his leadership and that the president's policies have made al-Qaeda weaker.

The document is also a sharp contrast to the platform adopted by Republicans at their convention. The GOP opposes abortion and gay marriage and would repeal Obama's health care overhaul law.