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WASHINGTON, Feb 22 (Reuters) - A modest job-creation bill advanced in the U.S. Senate on Monday as the chamber’s newest Republican bucked his party and sided with Democrats on a $15 billion package of tax cuts and highway spending.

Republican Scott Brown joined four other Republicans, 55 Democrats and two independents to overcome a procedural hurdle that sets up a final vote later this week.

Brown was widely hailed as a conservative hero after his surprise victory in Massachusetts last month gave Republicans enough seats to block most Democratic legislation.

His election prompted President Barack Obama and his fellow Democrats to call for increased bipartisanship, and an earlier version of the bill was written with Republican input.

But key Republicans withdrew their support after Senate Majority Leader Harry Reid scaled it back.

Brown said the bill was not perfect but would help put people back to work.

“I hope my vote today is a strong step toward restoring bipartisanship in Washington,” he said in a statement.

The bill includes a tax credit for businesses that hire unemployed workers, subsidies for state and local construction bonds and $19.5 billion to shore up a highway-construction fund.

Much of the cost is offset by a crackdown on offshore tax shelters.