Republican Rep. Joe Schwarz lost his party's nomination Tuesday, falling to a staunchly conservative challenger in a primary race dominated by a struggle over GOP principles that attracted more than $1 million in spending by outside groups.

Schwarz, a moderate who supported abortion rights, was defeated by former state lawmaker Tim Walberg. With 92 percent of precincts reporting, Walberg had 53 percent, or 31,869 votes, to 47 percent for Schwarz, or 28,168 votes.

Walberg, a former pastor, contended Schwarz's views did not represent those of constituents in the rural southern Michigan district. He vowed to vote against pork-laden spending plans, tax increases and the expansion of abortion and gay marriage.

"We have to believe that we won because the mission was clear, the message was clear and the agenda was clear,"Walberg said.

Schwarz, who was backed by President Bush and Arizona Sen. John McCain, was forced to defend his views on social issues along with taxes, immigration and spending.

The first-term congressman accused outside groups of trying to buy a seat in Congress by helping Walberg pay for TV ads. He said the primary was"probably a victory for right to life, anti-abortion, anti-embryonic stem cell groups but it's a net loss for the Republican party because it just pushes the party farther to the right."

In November, Walberg will face Democratic nominee Sharon Renier, an organic farmer.

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